I feel pretty lucky. I work for a sub of a Fortune 500 conglomerate. We have to book our travel through the corporate Web site and use the company MasterCard for all expenses. The Web site does stupid things like suggest a Hampton Inn in a suburb when you have meetings in downtown Chicago but it's OK to pick a more expensive place downtown. If you pick a higher airfare than the cheapest available you just say it was for "business reasons". (Usually the bargains involve long layovers somewhere.) Occasionally I find cheaper rates outside the corporate Web and my boss encourages me to take them.

No per diem limits. Receipts only for items over $50 charged on the company card and for items over $25 paid for by cash.

In general, I use the "would I spend my own money on this" test when spending my company's money. I'm pretty frugal but will spend extra to save my time or sanity. I've never had an expense account questioned.

My last job had a "no-receipt, no-reimbursement" policy- even for Garden State Parkway tolls. Very annoying. On week-long trips to HQ when I was staying at the Hampton Inn and buying stuff for dinner at the grocery store I had to attach all my grocery store receipts.