How do I check the health of a SSD?

We all know that SSDs have a limited predetermined life span.
So the question for me is how do I check in (Ubuntu) Linux what the current health status of my SSD is? And maybe an estimation how long it will take?

Graphical tool is preferred, but command line tool would also be fine.

I'm using Xubuntu 12.04 LTS

Install Gnome Disk Utility and check SMART Data and Tests for wear-leveling-count or similar. The higher that number (%, from 1 to 100), the more "used up" your SSD is, which means you are more likely to have problems. But if you have a recent SSD, you need not worry about it.

Installed via

 sudo apt-get install gnome-disk-utility

start it via

either menu->Settings->Disk utility

or via command line

sudo gnome-disks