problems ejecting USB drives, no force eject, list remains in devices list

Hello all. I have trolled the internet looking for a solution to this with no avail.

Basically, anytime I plug a USB device into my computer I have no way of ejecting/force ejecting/etc, I just have to pull it out/unplug it. From disk utility, it cannot unmount the drive because it says it is 'in use'. I've checked my spotlight preferences and have tried running some of the terminal scrips to see if there was something in use.

I have been having this problem for awhile now, and just ignoring it. However last week I ran a workshop and plugged multiple USBs into my laptop which has now resulted in a very long list of 'phantom' devices in my device list. They just don't disappear unless I reboot and I don't reboot that often, perhaps once every two weeks. It's simply anoying and my students don't appreciate hearing a chime after I unplug their USB sticks...

I have a Macbook Air running 10.8.3.