Most of the technology I work with today is driven from the top down (e.g. Java, XML) but it is the bottom up technologies that often offer the greatest real benefits and fulfil a real need. In this article, I'm going to list some of the more significant disruptive technologies and where they could take us.

Personal Computing

It may seem strange to list personal computing as a disruptive technology now that it is all pervasive but it is important to remember that long before the likes of Dell were selling us componentized and direct systems personal computing started out as a hobby for a few geeks. In fact, the big boys such as IBM didn't believe in it and it took a few upstarts like Microsoft and Apple to capitalise on this and earn themselves substantial wealth in the process.

Personal computing is the classic definition of disruptive technology I will use. It has the following traits:

* It is multi purpose and yet has no specific purpose
* It is open and standardised and eventually becomes just a commodity.
* It begins in the hands of a few dedicated non-commercial enthusiasts and is often adopted at a rate that the major institutionalised corporations just can't fathom. 
* It changes the way people work or live
* It has a killer application that makes it almost universally desirable

Personal computing may be games and office productivity to most people but that is not all that it is. It is music or video editing; it is a communication tool; it is an information terminal; it is a desktop publishing system; it is many things to many users.

The fact that it is highly commercialised doesn't make it a non-disruptive technology but illustrates how market forces are highly adaptive in mid- to long-term.

There is no need to even argue it has changed lives because whether it has improved them or not, the world of early 21st Century is quite different because of it.

Open Source Software

Open Source may be a political movement and have its ancestry in the work of Free Software movement but as a technology, Open Source offers something that caught a lot of people off guard.

The idea that open source / free software of high quality is available to replicate the work of most commercial software or in a lot of cases to provide better software than available from the commercial software is in itself disruptive. The fact that it became widespread and adopted by the technically minded illustrates how quickly a grassroots technology movement can gain ground.

What is most disruptive about this technology is the method by which it is created and the effect of building open source software has had. Closed systems have never had it so hard. Even proprietary technologies such as Java have had to open their doors to accommodate a shift in what the end users, developers, in this case, find acceptable.

Peer to Peer (p2p) networks

Peer to Peer started well before Napster but it was definitely the biggest commercial proponent (if you could classify its unsuccessful business as commercial) and it certainly was the killer app. Yet p2p is more than Napster or file sharing. The principle is used in providing anonymous web browsing, distributed computing (e.g. SETI@home), chatting and data storage. It has suffered a setback in its killer domain but it is definitely now mainstream.

p2p changed the way people view the edge of the network and its utility. It moved away from the Sun / Novell vision of the network dominated at the centre to a network which utilises the growing capacity and power at the edge.

It's direct cousin, GRID computing, is bearing fruit in the commercial world and people are finding ways to commercialise the Napster model of media distribution.

Ad-Hoc Public Wireless Networks

Like personal computing, the components or the underlying infrastructure of this disruptive technology is provided by industry but the manner of its use is a grassroots phenomena. Perhaps the most publicised example is that of Seattle but it is fast spreading across the world.

People are using Wireless networks to build communities and to circumvent incumbent telco monopolies. They are using it to take control away from broadband providers. The Internet may be a centralised and controlled network but these certainly aren't. They express much of the same sentimentalities for non-commercialism and sharing that has got the corporations scared about p2p and open source.

Now commercialisation was bound to follow and that is a sign that the idea is so popular that the bosses are taking notice but will they capture the mood? According to some it is not entirely understood by the mainstream media or the big corporations.

Personal Content / Personal Delivery

The dot coms tried to commercialise the Internet far too quickly for either the infrastructure (i.e. lack of broadband) or users were willing to accept. However, this has had a nice side effect in that broadband is finally becoming a reality for a lot of people in developed countries (and elsewhere) and the infrastructure is in place for a much more grassroots push.

At the height of the bubble, there was fear that the corporations would dominate content delivery and the content produced. Sure Microsoft, Yahoo etc. rule the roost as far as page impression is concerned but the fastest growing segment of Internet content is produced by individuals.

The next step is, of course, deliverying that content from your own broadband connection or hosted server. As costs for both are reduced the market place for advertising heavy free web hosting will deteriorate as web hosting becomes something you can do as easily as receiving a phone call.

The weblog is not something that any corporation could have initiated although some community sites do make a fairly decent living as commercial ventures. Corporations may be buying some of the popular ones but the idea that people can publish and be heard is something that is going to put pressure on the control the old media has over the decimation of information.

The key to the blog revolution is the communities that spring up to promote them. Whilst most Net users may never encounter them daily once you publish your own blog it becomes fairly normal to read others. As this becomes pervasive, because we all have something to say, the marketing effect this has is tremendous.

Personal Digital Agents

This is a bit of dream technology but the fundamentals are in place. Personal digital agents are programmatical software that performs tasks for you using artificial intelligence. Whether that is trawling the net for news on a particular product or company, preparing a set of references for an article or locating that elusive school friend they will be tremendous boons and will change the way we do things.

Agent technology has been in academia for a long time and its slow emergence in the commercial world (mainly in trading applications) is not making too much noise. As part of the Semantic Web agents are something still considered part of an ivory tower dream.

For Agents to be useful they will need to be smart and programmable with the same level of skill it takes to write an Excel macro. They need to be able to do a lot of basic things such as finding things on the Net or on p2p networks without any knowledge on the user part. They must also be able to construct solutions to complex problems with the minimum of fuss.

The key to agent technology will be that they must be multipurpose and built on open standards. Much of the underlying principles are there and there is some progress in making agent development simpler. Yet the technology has a long way to go and it will be sometime before it is ready for even the use of the general technology enthusiast.

However, if it follows the model of other disruptive technologies then it will happen far quicker than anyone expected and it will present us with a new world of opportunities and open up a whole new set of dilemmas for the business world.