I've been using Stamps.com for about a year now. It's remarkably convenient. You can print out postage online for just about any type of mail. No more arguing with postal clerks. You even can get discounts on some types of packages. You don't have to stand in line at the Post Office. It has some real value. I just used it to send out a bunch of copies of the new Steampunk Trails out to contributors and reviewers. Really convenient. My dilemma is I now will not likely have much mail to send out for quite a few months. And they charge a monthly fee to use the service. Ergo, I can't really justify continuing to use it even though I sure do like it. So, I struggle as to what to do. They even these cool Halloween digital stamps you can get, though I have no use for them I sure do want them.
They've also got a promotion where if I refer people I can get some free postage [and so can the friend], yet everyone I know seems afraid to try it. So, I fear I may have to drop it as a cost cutting move, though I sure do have a lost of reservations about it as I have liked the service.