IP address and local time in register.php

Hello, everybody,

in order to deter abuse of registering I would like to
a) show the user's IP-address on the registration screen ("Your IP address is: xxx.xxx.xxx.xxx - and it is being logged.")
and/or
b) include IP address and local time in the registration email sent to the new user.
Can you tell me which variables I have to use?
(Or better yet: where can I find a LIST of all available variables?)
Thanx,

Wilfried