This might not be appropriate for the Forum - so ADMIN - feel free to remove it.
DXWatch - DX Cluster!
http://www.dxwatch.com/This site has a powerful webcluster, with many filtering capabilities. There is also a special feature for registered users: A spot filtering notification service, where the user create his filters and the spots are delivered to him via email, icq, pager or mobile phone. This has proven to be a great tool to watch for band openings, DXCC catch, DXpedition monitoring, etc.
Personally, I just tried it out - I set my filter to just show 20 Meter's - noticed ZL50VK (New Zealand) running on 14.239 working a W5 station - waited for the exchange to complete - and worked him!
KE3W Nevins "Frank" Frankel
Temporary QTH: Centralia, Pennsylvania (USA)
http://www.ke3w.com