My wife is in the process of obtaining her college degree, and as such she often has to craft documents of various kinds. Since we run Linux on almost everything in the house, she is quite comfortable with the tools afforded to her due to my "thriftyness", not that she would want to spend the money on Office.
And Office is where the issue arose that had me looking at Portable Apps. Basically at home she has OpenOffice version 2.4, while at school she can use 2.2 of OpenOffice or Microsoft Office. The trouble is that they don't necessarily like each others files too much and in particular with spreadsheets and graphs it can get a little dicey. Add to that the fact that she needs to do some pretty funky stuff, and it gets to be painful quickly.
Since I had been intrigued by Portable Apps for some while, I thought I'd give it a look and it seems that there even is a Suite version that includes OpenOffice 2.4 (version 3 offers a beta version at this point).
I did a little playing with it and it sure seems to work well, but I think until I have my wife see how well it works for her, I won't be sure.
But here is the clincher: It also runs under Linux!
Yes, it's all Windows binaries but wine under Ubuntu seems to have no issue with it!
I'll have to play with that some more, but it sure seems like a great way to do a lot of things very portably.
Now I need to figure out if there is a good way to sync the Linux side with my thumbdrive.