There are not as many asymmetric cyphers as symmetric cyphers. One of the main ones not mentioned so far is DSS, but this has the problem that sometimes signatures can give away the key - for example if the same key is used for two messages, the key is revealed.
Since RSA is so strong, and Diffie-Hellman a good second choice, the other asymmetric cyphers do not tend to get used very much.