Unable to resize Lion partition I decided to do a clean install of Lion on a new partition, then after copying my stuff removed the old one. I'm now stuck with 100~ GB of free space and a 20 GB partition that Disk Utility won't let me resize... oops.



I really don't want to have to:


create a partition in the free space
install Lion onto it then copy my stuff (again)
delete the old partition and resize the new one


Is there anything else I can do?
Yes - boot to your Recovery HD and use Disk Utility there to perform the operation. If it's missing, you can download and re-install Lion which will recreate the Recovery HD.

It's likely the volume is in use or one file that is open needs to be closed so it can be moved.