i use a program called gladinet to sync to google docs. its a free program which adds the online storage (google docs) as a network hard drive on your computer, so i save everything directly there. you don't need to convert any files to google docs format.
They have a paid option with folder mirroring, unlimited transfers (free is limited to like 1000 files per action or something) etc, but i find this perfect for my use. never noticed it hogging resources, if it doesnt work for some reason it might hog bandwidth for an upload, but u can just push that off. once in a while i've needed to check their site for troublshooting, but its pretty good.
It works with just about every online storage i think, but i wouldnt trust microsoft. or better yet, why not upload to more than 1? u can probably add more than one google account too to get extra security, and remember, google has unlimited storage for docs in google docs format
and @asher - thanks, now i know how to link

i should bookmark this page