The best cam out there right now for the price is the Scoutguard SG550.
I purchased an 08' I40 a few weeks ago, and after not being satisfied with the trigger speed I am now selling. The 07 models are slightly better at 1.5-2sec. The SG550's I just recieved are far more superior. Not to mention the 550's are about the size of a coke can and can be secluded very easily. The 8AA batteries it takes to power these are supposed to be good for 5000 pics.
Take a look the great review on chasingame, they call it the must get cam for 08'
http://www.chasingame.com/reviews_scoutguard.htm