Programming editors are next. There really are not a lot of options for the Mac if you are looking for lightweight, inexpensive and free tools.
TextMate - The best native programming editor for the Mac. It is shareware and costs €39 for a copy. But with an excellent set of features and good support, it is worth it.
Smultron - A good native open source editor. Nothing fancy, but a very solid editor. Currently, (as of 10/2010) the developer is not going to release any new versions.
Komodo Edit - This is the free open source version of the Komodo IDE. But it still has a lot of features. Currently my favorite editor.
JEdit - An open source Java editor with a very active community working on it. Lots of plugins and useful features.
NetBeans - The only tool I use for coding Java. It really can make things a lot easier.