I just read a comment on the Dickey-John website that they have "a $300 discount on the MiniGac thru Oct 31st, 2009.  Check with your local dealer."  (does not apply to the Mini-GAC Plus model.)

Sounds like if you want to purchase a moisture tester, now is the time to buy.

Edit:  I also found this on the Seedburo website.  It has the MiniGAC-L as different from the Mini-GAC.  I don't know what the difference is - maybe it is a model made on contract for certain retailers, kinda like Lowe's and Home Deport will sell their own models from a national brand.  I don't know - I'm just guessing here.  Anyway, it might be worth investigating.