Until I got a job using computers all day, I used to do that sort of thing as a hobby. Now I'm glad to get away from them, but do still enjoy messing around with computers now and then.
In my day job, I do web development, primarily using the Symfony PHP framework.
I used to spend quite a lot of time creating games with Multimedia Fusion. Way back when I was an A-Level student, I started creating ASCII Pacman in Pascal which, although obviously not pushing back any technical barriers, has produced some interesting algorithmic problems to solve. If you're looking for an advanced text editor for programming, web pages or whatever, then I highly recommend JEdit (it's free).
I don't actually play computer games that much. However, I am into classic games and adventure games. One of my favourites is the Space Quest series (see Roger Wilco's Virtual Broomcloset and SpaceQuest.net). I've created a map for the underground labion caves in SQ2 which you might want to check out if you like the game.
I enjoy playing Capture the Flag, an excellent strategy game. I've created a map of Sheet's Heath in Brookwood for it which you can download here: HEATH1.MAP (8.21 kb). You'll need the full version of Capture the Flag for this.
I also like LucasArts games such the Monkey Island series (see World of MI and the Legend of Monkey Island) and Day of the Tentacle. Another set of games I'm keen on (although haven't actually played in ages now) are the Dizzy games from Codemasters. Visit my site Dizzy's Domain for plenty of info about Dizzy. Other games I like include Driver, Worms 2, Transport Tycoon and the Civilization and Settlers games.
Other computing interests
I'm a keen user of Wordperfect as it is far superior to Microsoft Word, being both easier to use and more powerful. It's a great pity that Word is currently the standard. WordPerfect Universe is a great WordPerfect site which is primarily made up of an excellent set of forums. If you're interested in seeing how WordPerfect and Word shape up when compared then you might like to check out the WordPerfect vs Word Centre.
I also highly recommend Opera for quicker, easier and more enjoyable web-browsing.
My Final Year Project for my degree was A critical analysis of Behaviour-Oriented Design (BOD), based on experiences in using it to create an Unreal Tournament Capture-the-Flag (CTF) team. The dissertation was published as a Technical Report, and can be found here if you press "Next results page" often enough (direct link to PDF).
My supervisor Dr Joanna J. Bryson and I co-wrote a conference paper based on part of the dissertation: The Behavior Oriented Design of an Unreal Tournament Character (available at Joanna's site or SpringerLink). Finally, I didn't write any of POSH Tools for Game Agent Development by Students and Non-Programmers (also available from Joanna's site), but ended up being included in the author list as it was about the work I'd been involved in.