I have the 2007 ACD 30" and no way at present to attach it to my new Mac Mini that arrived last night. I'm going to go to the Apple Store this afternoon to see if there is. MDP to Thunderbolt cable that will work or a MDP plug to HDMI adaptor. I've been told shouldn't be a problem. So far haven't seen the right connectors.
I am so relieved. It turns out that the Thunderbolt port on the new mini and probably many other Apple laptops, desktops etc. is the same size and works perfectly as the mini display port. I plugged (with a friends suggestion) the Mini Display plug into the Thunderbolt port and the ACD works very very well. I knew that Thunderbolt displays worked this way - but my 30" ACD is from 2007 and no where did anyone tell me to use the Thunderbolt port rather than wasting time trying to find an adaptor for the the HDMI port. So now I'm happy.
(Just saw that I have to change my signature ... my Mac Mini (2009) is now replaced by the 2012 mini. The iPad Mini WiFi + cellular is still processing.)