You can make your own smartpots out of that that "cloth" they sell at the hardware store, that's for laying on the ground and mulching your weeds. We made a sort of frame out of chicken wire. The cloth is cut to size, placed in the frame and connected to the chicken wire with zip ties. They're kinda floppy, but once they're filled with dirt, gravity will make them keep their shape.
Since we'll be using HUGE pots for the outdoor season, this is WAY, WAY cheaper than buying smartpots. A roll of weed cloth, a roll of chicken wire, and some zip ties. That's it! O yeah, it's easy for us 'cause these pots don't have a bottom--they'll just sit on the ground. If you're working indoors, you'll have to figure that part out.