On CSI I have identified:
SL Scorpion (That's the main, I think)
SL Strion (definitely in the pilot of CSI: Miami)
SL Ultrastinger (at the beginning)
SF M4 Devastator (a lot recently. I wonder what their budget for batteries is...)
Inova X5 (Grissom used a white one once, the UV version is sometimes used)
Most TV Shows/movies seem to prefer incans. My guess is that it produces better color rendition on standard film/cameras. Using flashlights directly is a pretty recent development. Up until the 80s standard flashlights seemed not bright enough for the used film sensitivity. Mostly people used an off-camera spotlight to simulate the flashlight spot (funny, when the movements didn't coincided). Later on (late 80s, early 90s) quite often bright incans with cables were used, since no small batteries with high energy density were available. The cables off course had to run hidden from the flashlight to the battery pack or power plug. You could sometimes see them (e.g. Star Trek TNG).