I've been having sick ideas of late, but they're far too sick to actually implement without serious amounts of time.
I'm thinking of ways to make Quantum::Entanglement more quantum physical than it already is. Currently the program acts as the observer (the thing which causes a superposed state to collapse). I'd like to make the person running the program the observer instead. This requires that I let the module follow every possible execution path (the physical analogue being the classic two-slit interference pattern). collapse would only be caused if one of the possible paths was examined in some way, by the program producing some output, essentially making the whole thing a really big, really black box.