Advanced Task Cleaner 2.0 is nice, you can specify apps to auto kill after a certain period, I have found it helps keep the device 'snappy'
If you are into DJ'ing then you must look at Andj it's a great app, pitch control, que points, retard and accelerate with touch, if that means nothing to you then move along...
AndroIRC seems to be doing a solid job as an IRC client.
Ethereal Dialpad is another music app, but certainly no skills needed, great for showing off touch screens those new to them
Shazam, again another good show off piece, play it a piece of music (commercial'ish works best...) and it'll recognise it and pull up the details.
Ustream Broadcaster and Ustream Viewer provide video entertainment and live video broadcasting from your handset (works pretty well on mobile as well as wifi)
finally for some fun, search for W.TV (sry trickyhenry, missed your post) and install it, its some chinese app and seems to have literally hundreds of channels, movie trailer (english voicetracks with subs), dvd's and other things too, anyone read chinese?
Edited by tudorw, 10 June 2010 - 12:10 AM.