It is a free plug-in for iTunes that scans your music library and finds when the artists in it are playing in your area. iConcertCal displays this information on the iTunes visualizer. Installation couldn't be easier. Concert information is automatically downloaded each week.
Sorry, PC people. This is Mac only, at least for now.
UPDATE/CORRECTION: Jeff from iConcertCal writes:
"Thanks for your blog about iConcertCal! I'm glad you like it. I just wanted to let you know that iConcertCal is actually available for both Macs and PCs. If you get a chance, would you mind fixing that line in your blog that says: "Sorry, PC people. This is Mac only, at least for now."You're welcome, Jeff! Sorry for the mistake, and thank you for the software.
Thanks again for spreading the word about iConcertCal."