I use a standard user account for my daily tasks on Mac OS. Since upgrading to Snow Leopard I am asked to do the following when a program is run from within Xcode:
\
After you run:
sudo dscl . append /Groups/_developer GroupMembership
per the answer above, you may still get prompted to enter in your own password:
We need authorization from an admin user to run the debugger. This will only happen once per login session.
What it really means is any _developer groupmember user so just your non-admin user/password will work here but to get rid of it completely (no prompts after a reboot) you'll also need to run:
sudo DevToolsSecurity -enable
(running it with sudo as an admin user/as root will make it so you can do it remotely without a gui password prompt)