^ Wisk - you sure you're not in Meril Lynch?
Honestly though that's how I operate. Just a few weeks ago I got a call form my pal regarding a potential client. I thought for a few minutes while he was babbling and then I interrupted him saying: " Can he wait?" Pal was confused but I made it clear that I'm occupied with work and after I'm done with my current client(s), I can spend some time with his friend.
I also stated the absolute maximum time frame including a worst case scenario to him so that by the time I'm free I can handle other projects with ease of mind instead of cluttering my life and disabling my nerve center.
Dwood - if you're reading this please come forth with the truth - running away from your obligations on the basis of being a kickass fabricator isn't actually professional IMHO
^mods - if this message is too harsh please delete it
Just trying to speak on behalf of my mates...