Eventually, I'd like to get Master's initials in the lock or something...but I don't know how I'd explain that kind of tattoo (even minus initials) to vanilla friends.
angelfreak - I think that's a great point that hasn't been raised here. While some of what we'd like to do in a BDSM context might look appealing and the 'right thing to do', it doesn't disappear when you go out to work or meet your family and friends. I think it's a major decision that has to be made:

how obvious or overt do you want your 'mark' to be to vanilla eyes? and
how comfortable will you be with people seeing it?

I think everyone going through the process of deciding on permanent marks (be it BDSM ones or not), should ask him/herself those questions.

For me, personally, this would pose two options - either get something that is cryptic enough so that I'd feel comfortable showing it off OR get something more obviously kinky somewhere easily conceivable if necessary.

mina - I like the matching dragon tattoos - so cool! Still not sure about the cuts...*shudders* Is there a chance that we'll see some of your marks at some stage? I'm so curious.