And now, the most EFFECTIVE combination entry is...
... Priest + 100% controlled motion.
Most, if not all, high-powered players know that some monsters have
resistances so huge that only a priest's harm spells can reliably take them
down. The sheer damage habo can inflict reliably is second to none, even
though it can't kill directly. However, this massive damage capability is
countered by an unusually long casting time. While powerful highbies can use
100% qc and 110% ql to drop this time down, even a lvl 50 boonless priest
could easily get some first-round lethality using this combination. The other
evil religous guilds would find it helpful too (especially tigers chasing down
a fleeing target), but combining the most damaging spell with (for all intents
and purposes) a guaranteed 1-round casting time makes this the most effective
result I saw.

The winning entry for the most ORIGINAL combination is...
... evil_religious + zapping 100%.
This has got to be one of the most dangerous pkilling combinations, and I am
kicking myself for not thinking of it first. Shadow leap + 2 wands of golden
arrow = mission complete, hasta lavista sucker. Reavers and spiders are both
capable of taking the beating you will most likely receive when you
reloc...and your wands explode, which tends to kill most mages in horrible but
amusing ways. Hell, give the priest a wand or two, something to play with
while his habo sloooowly tics down.
For general purpose adventuring, it might not be the best, but for sheer evil
originality, it was top dog in this contest.

Thanks to all who participated. TPs will be given out silently to protect the
guilty.

Shinarae Lluminus