[nateo]

I got my 8 gallon pet food containers because they had wheels on the bottom. Not necessary, but pretty nice.

[Hokerer]

Rubbermaid tubs here.  With the grains in plastics bags in the tubs.  Four tubs total...  one for 2-row, one for Marris Otter, one for grains with quantities larger than specialty but not full sacks (Pils, Munich, Wheat, etc.), and the last one for single-pound bags of specialty malts.

[BrewArk]

I put mine in plastic buckets.  When I am not using my fridge to ferment in, I place the grains inside the fridge to keep them away from any pests that may get in the garage.

+1
As I can get 5 gallon food grade pails w/air tight lids for free.  (a 50# sack will fit in two pails, and they stack well)

[dbeechum]

I've been using these in conjunction with 5 gallon pails. Gamma Lids. They're the same lid as on the vittle vaults, just adapted to work on a standard 5 gallon bucket.

As mentioned before, a 5 gallon pail will hold ~25 lbs, so easy peasy.

[morticaixavier]

I put mine in plastic buckets.  When I am not using my fridge to ferment in, I place the grains inside the fridge to keep them away from any pests that may get in the garage.

I am not sure this is an issue, but I know that with some things (like coffee beans) keeping them in a cold place can actually be detrimental as the switch from cold to warm and back again can cause condensation to develop in the container. Just some thign to keep in mind. I think the solution would be to package in 1 - 10 lb increments so you aren't taking a tub out, opening it and putting it back in over and over.