For C-41 developer, my favorite right now is Martinelli's apple juice bottles:

These bottles are 300ml and made out of rather thick airtight plastic. I make 1 or 2 liters of developer and split it into these bottles and use them one at a time for one or two shot development. The developer keeps very well in these. I just opened a bottle that I mixed 2 months ago and it's in perfect condition. The only trouble is, every time I open developer now, I want to drink it -- the juice tasted soooo good ;-)