Make Something Users Want
AirFoil, Rogue Amoeba’s awesome Mac/PC software, lets you stream any program that makes noise — from Songbird, the free media player, to your DVD player, to Virb.com in your web browser — out to your wireless AirTunes speakers. Super cool, and with the (included) SoundFlower extension, you don’t need to select which applications you want to stream; SoundFlower mixes and streams it all together. Perfect.

Make It Easy to Pay For
They accept Paypal - Done. Note to all small software / shareware companies — no one wants to use your shady e-commerce system. Yes, i know it was a big deal to get it set up, integrate it with your site, etc etc. Just use paypal. I shouldn’t need to give you every piece of information about myself just to send you 20 bucks. Please? Thank you.

Make Me Feel It Was Worth Paying For
The instant you enter your registration code, a sweet little “diploma” certificate-of-authenticity thingy pops up, “proving” what you just bought. I love this idea. I’m not going to post a screenshot of it because it was a nice surprise, and it wouldn’t have been as fun if I had already seen it. It’s like the toy in the cracker jack box — it’s not the dollar value of it that makes it fun, it’s the surprise value.