If by chance, you are like me, and the first time that you ran Eclipse Ganymede, you were greeted with an exception screen like this one:
Here are the steps necessary to resolve that issue:
1.) Navigate to your $ECLIPSE_HOME directory (the directory where you installed Eclipse)
2.) Copy your eclipse.ini file, for backup purposes
3.) Open your eclipse.ini file and modify it to look similar to this:
4.) Try to start up Eclipse again, and hopefully your problem should be solved
The main problem seems to be that the initial settings does not allocate enough memory for Eclipse to run. By adjusting the memory settings, by using the example eclipse.ini file that I have shown, you are giving Eclipse enough memory to start up.
This interesting thing is that this issue does not seem to affect all installations. The "vanilla" Eclipse Ganymede that I obtained from Eclipse worked on one of my machines, but not on another.
If this helps, please pay it forward.