WOW.. I completely forgot about this thread. I've been on the Delorean forums about this subject.. Needless to say, there are so many projects.. From a cool SBF, a 2JZ, 3 rotor, GNX V6 to a usual Small Block Chevy (the most popular for any engine swap in any car).
I have not seen anyone do a swap for a Porsche 911 engine and transmission. Nor something like the Alfa V6 engine, which would be nothing less than awesome; since that Alfa engine is one of the best engines ever made.
Another great swap would be the Jag V8.