The price of US postage stamps has been going up, but at 44 cents, they remain an amazingly good value.

Using a single stamp on a regular envelope, you can send your rent check to the landlord down the block, or to Florida.

The other day, stuck with some leftover Simpson's stamps, I got to thinking, "What is the break-even point? At what distance is it cheaper to mail the check versus delivering it yourself in the car?"

It's a fairly simple calculation. Take the price of gasoline and divide it by your car's rate of fuel consumption to obtain your price per mile. For example, if gas is $4.30 per gallon, and your car gets 28 miles per gallon, your price per mile is $4.30/28 or 15¢ per mile.

Next, divide the price of a first class stamp by your price per mile (in this example 44¢/15¢) or 2.8 miles.

2.8 miles is the total distance you can drive for the price of a stamp, but of course, you will have to make a round trip, so the maximum distance driven to deliver a rent check should be half that distance, or 1.4 miles.

Here's a Google Map for reference, if you don't know how far 1.4 miles is. (In Sacramento that's the distance between Olive Garden across from Arden Mall to Dimple Records on Arden Way.)

It's five minutes of driving in the city, or 25 minutes of walking. If you are delivering a letter any further than that, it's cheaper to just mail it.