Many of us in Ham Radio like to chase DXPeditions to work those 'rare ones'. I'm gonna share a tool with you I've used for years that you may or may not be aware of. NG3K built and maintains one of the most comprehensive listings of DXPeditions I've ever seen. You can see what was, is, and will be active for the current year. You can click on the active operations and see spots for just that call without having to fiddle with filters in your DXcluster interface. Very often there are links to other info on the DXPeditions.
I use it all the time to keep up with what's going on and what's coming up. You can see his page at: http://ng3k.com/Misc/adxo.html .
I also have it embedded in my website at: http://www.ipass.net/wb4iuy/radio/wb4iuynew8d.htm .