From the railstand position, there are many tricks you can do. These kinds of tricks are great to add to what you can do, and most look pretty impressive.
Railstand Tricks - Body Varial
While standing in a railstand, crouch down a little, jump and spin in the air, and land back on the skateboard. If you were in a toeside railstand, jump and land in a heelside railstand! This is a great trick to start with.
Railstand Tricks - Rail Flip
This is tougher, but give it a shot. While standing in a toeside railstand, scoot your back foot back so that your toes are right on the rail / edge of the deck, and a little towards the tail. You want to be right on the ball of your foot. Now, in one smooth motion, jump up with your front foot and kick the board forward hard with your back foot. Pull your feet up high to get them out of the way, then land on your board. It's very important that you remember to lift your front foot off of your board
just before kicking with your back foot.
Railstand Tricks - TS to HS Rail Flip
This is where you start in a toeside railstand, then flip the board and land in a heelside railstand. This trick is done just like a rail flip, but kick harder! The trick is to practice enough so that you start to feel when the board has spun just the right amount for you to put your feet down when you are jumping and catch it. It might help to not have your back foot towards the tail at all. If you have problems, try scooting your feet around a little first.