Stay up forever!!!

If your stamina gets low and your character is feeling drowsy do this:

(WARNING: Make sure your character is drowsy before doing this, otherwise it won't work!)

1) eat anything that will get the green in your stamina bar gets about 3/4 or almost full. Broiled blowfish (use the bonfire set to cook the blowfish) will give you a BIG stamina boost.
WARNING: Sometimes your character will get sick from eating broiled blowfish and it could cause you to lose some of your stamina instead of gaining - BUT eating the broiled blowfish won't land you in the clinic. A boiled egg is another good cheap stamina booster.

2) eat a salted cureall (use the bonfire set to cook the cureall) - that's it! Your stamina should be full strength and your character will no longer feel drowsy! It will last a long time too! Make sure to repeat when necessary (when your stamina bar gets low and you're drowsy again).I've tried this out and it really works. Remember to keep a supply of salted cureall and cooked food in your fridge!