Another Tack on the Royal Flush

[GrunchCan]

You are observing a 7-handed game of texas hold'em. What is the probability that by the river someone (or everyone) would have a royal flush, if they stayed in the hand?

In other words, if nobody folds and all seven players show down, what is the probability that at least one player will have a royal flush?

I think I know the answer, but I don't want to taint the replies, and I want to check my answer (a friend of mine came up with the answer when I couldn't figure it out & asked him).