Update: this project is now in public beta. You can download a copy of Pete's Aion Radar at aionradar - Project Hosting on Google Code. It has an auto-update feature that will check for new versions every time you start it. It requires the .Net framework 3.5 (with latest updates) from Microsoft and you must run the game in windowed mode (maximized windowed mode is fine too).
This project is released as freeware open source under the GNU GPL v3 license. Please provide feedback at AionRadar (Gmail address), but report bugs and feature suggestions here.