My lab uses about 50 liters of LN a week and I think we pay around $50 for a tank fill. We are using the high pressure tanks that are 5ft tall and about 2 ft around and they last upwards of a month depending on our load. The cost of the tank and the dewars is substantial though. The small 8L flasks we use for evaporator trap and EDS cooling take at least 4 days to bleed off on their own. When we leave them full on friday they are still more than half full come monday. The 50L low pressure flask lasts a few weeks but it a huge PITA to deal with because of its bulk and weight when full.
When I do screwy culinary stuff at home and need LN, I usually just dump a few liters in a styrofoam cooler then put that in a normal beer cooler. Its fine for a day or two and I've never had one break. Most people get twitchy handling it at first but it is pretty easy to deal with. No need to drop the coin on a commercial dewar if you only need to use it briefly once in a blue moon.
If you are using it often, don't bother with the dewar then either. Buy a high pressure tank and then poke around on the culinary forums for instructions on building the dispenser. It is easy and way way cheaper than the off the shelf ones. Better too from most accounts.
-Sandow
