I love circuit training, too.
Hands down, alltime favorite workout DVD ever:
Women's Health Ultimate Fat Burn with Amy Dixon. I think it rounds out at 38 minutes, which is shorter than you want--you could add on something for your abs after. You have to not mind TIFTT, though, as the routines repeat within each circuit. She has a longer workout with (I think?) a similar format,
Super Fit Bod, but I haven't ever done it. Although it's in my "to preview" stack at the moment!
I think Sharon Mann used to put out some nice circuit workouts, too. I have two of her ultra-programmable DVDs, but it's kind of hard to tell what's what with them.