Usually I spend one brutal afternoon each spring, just raking by hand back into the driveway. Doing both sides of 800+ feet of drive is pretty awful on the core muscles, but I haven't found any better way that doesn't put a bunch of sod and mud back into the gravel also. The generator and shop vac idea sounds worth trying.
But the main thing is, to avoid putting the gravel into your grass in the first place:
- Plow gently when ground is mushy - I flip my rear blade around backwards when needed. Or just dont even plow the 1 or 2" snows.
- Don't go nuts and plow way off your drive sides, just put it right to the edges of the drive itself (helps to have a 12+ wide driveway for this)
- when the snow pack ridges start to thaw out, you can plow it back onto the driveway to melt there instead, dropping gravel onto the driveway again. this one is tricky, because I hate keeping my driveway more wet and mushy than it needs to be.
Or, you can just not care, and let the side grass eventually consume the lost gravel.