I have 8gb flash drive with windows 7 sp1 installer + folder called "Basic Programs"

7zip
Adobe Flash Player
Adobe Reader
Adobe Shockwave Player
Chrome
Comodo Internet Security
Everest 5.50
JDownloader
JkDefrag
K-Lite Mega Codec Pack 7.0
Magic Disk
Magic ISO
Nero 10
Notepad++
OpenOffice
PeerGaurdian 2
Skype
Spyboy Search & Destroy 2.0
SugarSync
Teamviewer
VLC Player
Your Uninstaller
Windows Live Messenger
Windows Loader v2.0.6
WinRAR 4.0
Everest 5.50

All programs on the list + some others i use only = 1gb

I still have over 2gbs space on my flash drive. but i just use that if i have to add another program or if i need some storage.