Doc's to go is great for spreadsheets. I've paid for it on my last 4 phones (4 years). It's been very worth it. I would be lost without it!
There is a cheap $3(i think) one called "spreadsheet pro" or something like that. It was horrible. It does what it claims to do but won't open ANY other kind of file. It only uses it's own filetype. Something off the wall that no other program/system uses.
[><] Deo Vindice [><]