I wish more apps were portable

PortableApps.com

Even if you're not going to be transporting them around on a USB drive, it's still nicer to install portable apps on your machine because

1. no messy install/uninstall and ugly registry messiness
2. all settings contained with the app
3. easy to backup/restore and transport

Of note:

1. irfanview (graphics viewer)
2. filezilla (FTP client)
3. google chrome (browser)
4. opera (browser)
5. pidgin (IM/chat) 
6. skype (video chat) 
7. utorrent (file sharing)
8. Sumatra PDF Viewer 
9. 7-zip (file archiver)