When the FO says, "hey ya'll watch this" and the captain doesn't know enough to intervene. . . it might be a regional jet.

If you can preflight the elevator with a running start. . . it might be a regional jet.

If the first time you see the thing you think, "wow, that's tiny". . . it might be a regional jet.

If when traveling revenue and forced to "gate" or "valet" check your bag only to not get it at the other end due to the crew tags. . . it might be a regional jet.

If your approved carry-on crew bag only fits in the closet. . . it might be a regional jet.

If your approved carry-on crew bag has a rainbow of gate check tags. . . it might be a regional jet.

If you have to name several airlines when asked who does your company fly for. . . it might be a regional jet. Frontier, Continental, United, JetBlue. . .
If you're the third company flight to land in succession and each goes to a different airline's terminal . . . it might be a regional jet.

If you've been furloughed after a year on the job and still don't qualify for the ATP. . . it was a regional jet.

If you've been furloughed and the CFI job you go back to pays more. . . it was a regional jet.

If you've been furloughed and you don't qualify for a CFI job, you went from zero to hero to zero all because. . . it was a regional jet.