Wishlists
Some of the PEAR developers have wishlists at Amazon or a similar service. If you appreciate the work of a certain developer, feel free to buy something for her from her wishlist. To find out if a developer has one of those wishlists, go to the account browser, look for the details of the developer and there you'll see if she has a wishlist. Buying something from people's wishlists may even speed up the time in which annoying bugs are fixed ;-).