Facing the challenge of keeping a clean bench, limited space, constant inspections I had a bit of a breakthrough recently when visiting H's storageworld. They sell a narrow plastic tray, wide enough to fit my Macap in, deep and long enough to allow me to collect (I reckon) 98% of the grinds as I fill the portafilter and level etc. So far its been very useful, was about $10 if i recall correctly, and i use the grinds caught to do my post-cleaning reconditioning shots.
Will post a pic or two if anyone is interested but it has definitely made a real difference for me in the battle! Nothing like a little bit of "breathing room"!