Are you referring to the
address or the
private key?
The trick is, you can generate or make up the private key yourself. So you can have something that is easy for you to remember, but hard for others to guess or brute force.
The address, however, is different. It's a double hash (sha256+ripemd160) of the public key that corresponds with your private key, and thus totally random. There is no way to have an 'easily memorable' address.
Although.. The concept of FirstBits kinda did this, especially in combination with vanity addresses. Although it had some potential security flaws (one typo in the first few characters = money gone to wrong address) and it doesn't seem to be supported anymore. At least not by blockchain.info and firstbits.net
As for easily
reproducable private keys, you may consider a brain wallet. Requires you to remember not the private key or address, but a passphrase (from which the private key and address are deterministically derived).