FlashFXP
Winrar
Alcohol 120%
MIRC
IE
Winamp
WMP
Notepad
Explorer
Adobe Acrobat Reader (I *LOATHE* .pdf, but it's a necessary evil)
I'm sorely tempted to list Powerstrip, because it is probably the single best small app I've ever come across - but in truth, I could just about live without it (assuming I have an nvidia gfx card). It has incredible scope and works with pretty much any gfx card from the last 10 years.
At work, I need:
Office
Remote Desktop
Test Track Pro
Telnet
Putty
IE
Notepad
Explorer
Adobe Acrobat Reader