Rebates? How...

Is it bad to buy stuff that I send in for rebates to get the item(s) free? It's not like I'm spending the money and never get it back, it just takes 4-6 weeks to happen.

So, I just need to figure out how to keep track of this stuff...do I use Post-Its, make an Excel spreadsheet, post it on this blog? All three? I just don't know.

I guess I'll post it here, and make some sort of a note to myself, probably Excel. This way when the rebate check arrives, I know which card and how much to pay back.