I use Stamps.com. It's cheaper than a postage meter and obviously more convenient than going to the PO. I have a small consulting business where I send maybe 30 flats a month to six or so addresses. Stamps.com stores the addresses so it's easy to print the mailing labels with postage knowing the addresses are correct. I did buy forever stamps at the PO to use when I send checks but anything I send to clients goes with either the stamps.com labels or stamps.com stamps. The stamps look enough like USPS stamps that they do present a nice look. Two minor negatives: (1) they do not print forever stamps; (2) they do not support return addresses on the labels I use so I have to add a sticker for the return address.