International Phonetic Alphabet (IPA) Unicode “Keyboard”: A Unicode replica of the official chart written in XHTML/CSS and released under the GPL. Allows the user to type strings of IPA characters while keeping track of previously used symbols and optionally outputting XML entities.
IPAScript: Description and online Demo of an input system for generating IPA symbols from SAMPA (Ascii) keystrokes
Say...: Text-to-speech translator which also reads ASCII representations of the IPA.
The IPA in Unicode: Unicode standard used by current browsers covers all the IPA phonetic symbols. Listed with their meanings, codes, and advice on Unicode fonts that contain them.