Cat left 'present' in kitchen but its still alive!! help!

Don`t let it suffer ,get the neigbour. Failing that a sharp tap on the head with a garden trowel will end his troubles.Not nice but needs do be done fast.

After reading this my wife and i feel lucky our offered rabbit last week was dead!

Good Luck

Thank goodness! I just read this thread and was worried the neighbour might just kill it.  If there is no obvious injury then I think he deserves a fighting chance. If he is old enough to be eating on his own he should be able to survive. I work at a sanctuary and we have had several little rabbit presents in our time. If they appear uninjured and come around from the shock we either release them straightaway or feed them for a day or two if needed.
Keep him somewhere dark, quiet  and warm but not where he will get too hot shut in his box. The shed sounds good.  Obviously he needs air holes, a bit of hay/straw to cosy up in and some grass to nibble. A shallow dish of water would be good but if the dish is light he might knock it over.
Be aware that if he is in a cardboard box he might chew his way out before morning. Also, wild bunnies have a nasty habit of appearing fine and then just keeling over so don't be surprised if he dies in the night. You can only do your best. Sounds like you are on top of things after your initial panic.  blooming cats.  Why do we have them?