I did a little math, and with the Staples multipurpose paper we use, that works out to 3.44 cents per page "real world". By contrast, our HP DeskJet 5650 would run an estimated 12.56¢/page on the Staples paper. However, we don't feed it "the cheap stuff" -- with HP's less expensive inkjet paper, the cost per page rises to 13.46¢
But what about the power? Our LaserJet 6mp draws ~400 Watts when printing, vs. the DeskJet 5650's 30W. The LJ 6mp is rated at 8 pages per minute, the DJ 5650 at "up to 7.7" in B&W and "up to 5" ppm in color. Let's use the B&W rate. So, to print 1,000 pages would be 125 minutes for the LJ 6mp. At 400Watts that's 0.833kWh (kilo Watt-hours). The DJ 5650 would run for 135 minutes, consuming 0.068kWh. Our utility rate is ~$0.16/kWhr. Power, plus materials, means that the LJ 6mp churns out those hypothetical 1,000 pages for $34.53 vs. $125.61 for the DJ 5650. That would be 3.64 times more per page than the laser printer.
The moral of this story is that if you print any volume at all, a laser printer is the way to go.