Theres the HPWhore Soldier: Black Box, Concheror, Half-Zatoichi
the ever famous M1+W Pyro or Engi butt buddy: BackBurner/Phlogistinator, Maul/Homewrecker
Nest Camping Engi: Mostly Jag/Southern Hospitality, Short circut, Widowmaker/ Pomson 6000
and one I like to use just to screw around
Cyborg engi: Pomson 6000, Gunslinger, short circuit (Gotta admit it's funny when you get a kill with this XD)