RanGra: Some other things to consider. What style of beer are you trying to carb? That will determine how many atmospheres you want it to end at. I tend to shoot for around 2.5 for most of my beers and can get it there pretty quick if I lower the temp in my kegerator and jack up the psi to 30ish. That said, you want to do two kegs, so you may end up with one that is properly carb'd and one that is a little flat, without having some sort of tee/manifold. As Yooper said, there is another way where you roll the keg and agitate the beer to get the gas to dissolve more quickly. I have not had a lot of luck with that method, but others have (see YouTube for many videos on how it is done). Since you are in a predicament, you may want to try it but I find it usually ends up with an overcarb'd. foamy beer that is probably worse than a slightly flat beer. I also dry hop in the keg and this method does not work well with hops as you get a lot of hop "boogers" in your beer. Best plan is to run to the LHBS in the morning, get a manifold, and follow the advice above. Best of luck!