For me it's easy. There are three things I like about the computer: Tom The Dancing Bug, Crayola Art Studio, and Wordnik. All other activities require sweet sweet loudness in order for them to be tolerable.
Question - how do you focus on your work at the computer with all that fun within fifteen feet away? I usually keep mine in a locked shed and throw the key into a large pile of hay so I don't get distracted.
Actually, not true; I usually just get distracted.