Is there a command line utility that I can use for executing X based applications that will detach my applications from the terminal so they aren't closed if the terminal is closed?
I guess such a app could be called something like
nohup $1 > /dev/null 2>&1 &
Yes, there is a way to do it: first you need to run your GUI app and send it to background, then you (probably) want to detach it from Bash task management. For example if I wanted to run gedit this way:
gedit & disown %1
After that you can close your terminal window and gedit will not be killed. Enjoy!