Raddle seems to be growing pretty quickly, which means it'll soon begin to attract attention from our enemies. To avoid a complete shitstorm when a techy fascist finds out about us, we should put some better measures in place to protect against vote manipulation. Here's my suggestions:
Update the captcha on the sign-up page, it can be solved somewhat easily with a variety of Python libraries
Make sure that one email can't make more than one account. Right now you can make as many accounts as you want using only one email.
Require email confirmation before allowing voting and posting.
There's probably a lot more we can do, but this is a good start. I made a simple Python script that creates accounts and mass-upvotes using the zombie accounts in an hour or so, and it's way too easy. Let's prepare for an attack before it gets here.