I like to announce my latest plugin that makes it easy to display a link to your TipiT tipjar in posts. Also includes a sidebar widget and a customizable shortcode.
Tipit Suite does it all.
TipiT is a really simple way to give (small) donations to weblogs, websites or any other form of content. In order to give a donation, people don’t have to be logged in, or even registered already. This can be done after giving away the tip.