Vanitygen is a command-line vanity bitcoin address generator. If you're tired of the random, cryptic addresses generated by regular bitcoin clients, you can use vanitygen to create a more personalized address.
The example below illustrates a session of vanitygen. It is typical, and takes about 10 sec to finish, using a Core 2 Duo E6600 CPU on x86-64 Linux:

$ ./vanitygen 1Boat
Difficulty: 4476342
Pattern: 1Boat                                                                
Address: 1BoatSLRHtKNngkdXEeobR76b53LETtpyT
Privkey: 5J4XJRyLVgzbXEgh8VNi4qovLzxRftzMd8a18KkdXv4EqAwX3tS