If you shop around you can by an air compressor with brad nailer or stapler pretty cheap. I bought a Wen 2 hp 4 gallon pancake tank with brad nailer for $149.00. I've since picked up an automatic tool oiler and other gagets on specials from Harbor Freight. With a little expermentation I've found that 1 inch 18 guage brads at a setting of 75 psi works best. Drives them flush and doesn't split out the wood. However, there is still the problem of hitting a knot and having the brad curl back through your finger or hand if not careful. With the jig and double nailing each end piece to the top bar it takes about 20 minutes a jig full. That includes set up and removal.
I made a jig (I think Maddox posted a picture) that holds 17 frames. I had wanted it to hold 16 because that would make 2 supers worth of frames in one pass. But I mismeasured a tad and it will hold 15 with topbars all up or 17 with top bar up, top bar down, top up, etc.
Look around Ace, Lowes, Home Depot, etc, often offer a combo compressor/nailer combo at a reasonable price from time to time. If you want to go all out Harbor Freight offers a 3 hp compressor with 5 gallon pancake tank and a stapler, brad nailer, and framing nailer for $329.00 complete. I think it's a Port Cable brand name.