I'm finally getting somewhere on a similar idea, but it wasn't a maximum gears idea (I may still try it though. it would make for a crazier burrito bike). I'm trying to get a better chain line. I need an idler to clear a suspension pivot on one of my stretch cruisers. I've been using a skate wheel with two grooves cut in it, but I'm trying to add a bracket for a three speed trike hub where the skate wheel was. I'm going with a 7sp freewheel on the back for a 21spd, but a sram dual drive and/or a triple front crankset, would kick that number up to crazier (though probably some duplicate) numbers.