It makes things taste better for your partner when things happen and they can help your erection!

http://nutrifile.com/693/tips-for-male-sex-organs-vitality-stay-healthy-and-strong.html

Does anyone care to assess the nutritional value of dolls and gents, respective, nectars.  I am curious?

Scoed, keep it up with the posting, and other things.  

Sperm.
http://www.dontspitswallow.com/cum_nutrition.shtml
http://www.sementherapy.com/

Female ejaculate I could find very little info on but it has few or no calories so it will not make you fat.
http://wiki.answers.com/Q/How_many_calories_are_there_in_female_fluid