(Using Win 7 1440x900)

Okay, this is almost a stupid user trick but it's not entirely something the user would expect in order to avoid. 100% reproducible.

At times you may want to move the LOL "pre-game" client window to the side (to see vent window, check an icon on desktop, etc). Normally, you can just move the window back if need be. However, if you bring up a character summary, you cannot close the window if the X to close it is off-screen due to the placement. When this occurs you cannot continue with the game without exiting and relogging.

To reproduce:
1. Launch LOL
2. Move the window to the user's right by click-dragging the top of the LOL client's window. Move it about half-way off-screen (Doesn't have to be this much but easiest to replicate)
3. Go to your player profile
4. Select the Character tab
5. Click on one of the Characters

At this point you will be unable to close the window due to the X icon for closing being off-screen. Furthermore, you cannot drag the window back due to the character's screen being open. As a result you have to force quite through Windows and then relog.