Do you know what today is??
There are so many wives tales out there to "help" you figure out what you're having, the Chinese Gender Chart seems to be the most popular.
Some of the funny gender predictor tests, which I haven't done, include the baking soda test and the cabbage test.
Both of these tests require mixing the "ingredient" with urine. The reaction of the urine with the baking soda or cabbage is your predictor...I think I'll wait for the ultrasound!