Are you a fan of the Mozilla Firefox browser? If you are, and regularly work from a flash drive try Mozilla Firefox, Portable Edition.
Once downloaded to your flash drive you can work on any PC as if you were at home. All of your bookmarks are there along with any add-ons, e.g., Zotero. Other options to download are portable versions of open source programs like GIMP (a photo editing program) OpenOffice, VLC Media Player, and for fun Sudoku! The only thing you have to remember is that you can only run one version of Firefox at a time (but using another browser such as Internet Explorer on the desktop is OK).
For Mac users there is a browser-only version.