First- Flava Flav is the hype, boyeee! I will brook no mockery of the Flav. ( The big clocks, on the other hand, ya can mock all ya like- but Flava Flav knows what time it is...)

Secondly, a 4" Odorsok is $50 @ my local- why re-invent the wheel?
'Cuz a bag of the right carbon (intended for use in air filtration, as opposed to "suitable") is gonna run ya a lot more than $50...

I toss old filters, rather than refill them, for this very reason- filters are cheaper than carbon. Something about economies of scale...

If yer goal is to build it yourself just for the satisfaction, well, good for you- but if yer trying to save a couple bucks, just buy pre-made. It's cheaper, it works better, and you can spend the time you save tweaking other things to max yer return.

Anyway, my $0.02 US- not worth much to start with, but down 47% since W took office. Hell, ya wanna save a couple bucks- Vote against McDubya... SOB'd cost us a fortune...