quick square root axes

Dear R users,
while I enjoy the built-in log argument to the plot() function, I wished it
would be as easy to create more general custom transformed axes such as
sqrt(), logit, etc...

for example, instead of
 plot(x=exp(rnorm(10)), y=(1:10)^4, log = "xy"), sth. along the lines of
 plot(x=exp(rnorm(10)), y=(1:10)^4, trans = list(x = log, y = sqrt))
to encode the desired transfomation.

This involves just transforming the xy values and creating nice tick marks
at the appropriate positions.
Before trying to write my own function, I wanted to see if that
functionality already exists in another package ?