Hi Stewills
Any dark place, with a relatively stable temp environment.
Linen closet works well for me - it's got more beer in there than sheets.
Keep in mind that if the temp is low (less than 18deg) it will take longer to carbonate. If it's too high (like in a shed during summer), you might get some weird tastes - or may not....
Some guys get a cupboard and dedicate it to their bottles.