Here's what I do with receipts:

If it's something I'm going to keep for a while (electronics, bike gear, etc.) and it's expensive enough to be worth pursuing warranty replacement or repair, I put the receipt in a folder called, you guessed it, "Receipts."

If it's tax-related, which, for me, is not much, it goes in the appropriate year's Tax folder.

Car maintenance (both cars) goes in the Car Repair folder. I rarely look in here, but I feel good knowing I can find out when I replaced the timing belt last. (If I'm good, I'll note that in MS Money with the charge for the service, also).

I don't really have a process for more day-to-day receipts like restaurants and groceries. I don't keep those, I'm not sure why I would. I put everything possible on a Discover or REI Visa & use MS Money, so I have all the data I could want for tracking. I'm a recovering accountant, so I balance all accounts at least once a week, so I know what's going in and out.

Every now and then, again, no set schedule, I'll go through the Receipts folder. There will be some things I'll keep like an appliance receipt, and several things that I'll toss, like the receipt for the out-of-warranty USB drive I bought last year for 3x what they sell for now.

One thing I see in a lot of these "receipts" discussions is a compulsion to be really granular with where one files receipts. It's not that hard for me to breeze through a folder when I'm looking for a particular receipt. My approach is to do just a little thinking at the time of filing (keep/toss; tax/car/other) and then do a minimal, low stress review when I feel like it.