I've got a 5D and 40D. Three lenses always in the bag are:
1) 17-35 f2.8L (My favorite lens at this time.) Went on a field trip with my son's 3rd grade class today and this was the only lens I used.
2) 28-70 f2.8L (Good general purpose, candid portrait lens)
3) 70-200 f2.8L (Exceptional IQ and AF, Studio Portrait, Wedding, Sports, Wildlife, Air Show, etc. etc.)
I also carry a EF 100 f2.8 Macro and EF 50 1.4. The AW200 Slingshot's a good size bag. Still debating whether to add a 100-400 L IS or wait a bit to see if there will be a newer offering in this range.
I always carry at least one flash (Quantarray 9550 or Vivitar 285HV) with Cactus V2s wireless for the Vivitar, a Demb diffuser, gels, cloth, spare AA's, 77mm polarizer, release chord, zip lock bag, mem card reader, and extra 2G Sandisk II CF cards.
I use a duffle for all of the extra location shoot stuff, but everyday my Slingshot goes with me whether I'm planning on taking photos or not. Most of the time I take just the 5D and 5 lenses and strobe. Sometimes, I'll for go the strobe and tote the 40D along too. Use it with the 70-200 and the 5D with the other lenses. Did that this past weekend at the church picnic.