As was already stated, Excel will open a csv file no problem. If you want, you can even rename it using a .xls suffix to fool everyone into thinking it's a native Excel document. That's what I do, but a) I don't know any better and b) I don't have to worry about getting fired for being a liar.

Update:
My data is not comma delimited, it's tab delimited. I can't say if this works with comma delimited files (without lying, that is). Disregard my worthless advice.