There are apps that you most commonly use at home and at the office. This post will list my home apps:
1. iTunes - sync music and podcasts to my iPhone.
2. Yahoo Widgets - Wifi, weather, battery, cpu, clock widgets
3. Thunderbird Mail - I am more productive reading mail with Thunderbird than Gmail
4. Miro - iTunes cannot play everything, discover other podcasts Apple wouldn't show
5. VLC - a must have to view any video format under the sun. Never fails!
6. Notepad - duh
7. Command Prompt
8. Firefox - duh
9. CDBurnerXP - on Windows, K3B or Brasero on Ubuntu
10. Boxee and Plex - Media Center
11. Winpatrol - UAC and random settings for XP
12. Digsby - Best IM Client for Windows
13. Visual Task Tips - thumbnail review like Compiz and Vista/Windows7
14. iPhoneBrowser - just installed, browse iPhone internal directories
15. VirtualWin - toggle through multiple desktops on Windows - Spaces on Mac, Compiz
16. Update Checker - still beta but awesome tool to check application updates
17. Defraggler - a much better defragment tool for Windows
18. CCleaner - if you don't know this and run Windows.. you're in trouble
19. Ad-Aware - you're in trouble...
20. Avast - antivirus!
23. Twhirl - just installed for Twitter, needs Adobe Air.
You get the picture, there may be more but I can't think of them right now..