Yeah you can do that, but I don't want to have to search out an email for a file, then download it time and time again when I want to view it....
I have just seen this, which is in the early stages and needs more revisions to gain full office doc support;
http://www.v1ru8.net/mightydocs/
Google Docs is very usefull, and I've already got a bunch of files uploaded onto it so that I can access them on other computers (works, friends/family computers etc - I initially did it so I could access a couple of docs whilst I was going to be away in the US - very usefull to be able to walk into the Apple store in NYC, open Google docs and view the info I needed!)
That MiGhtyDocs app looks like it could be usefull as it allows caching of the docs to the iPhones internal memory, so with a little work (more file types supported, like .xls, .pdf, .pps) and folder support, that could be the one!
Back to the topic in hand tho - still at a quandry as to what to do! second hand 2G, unlocked to T-Mobile for probably £200ish, brand new UK 3G locked to o2 (pay & go) for a year and hope the Dev Team cracks the unlock in that time, for £350, or import an Apple-unlocked 3G from Italy at a cost of probably £500......