VSCommands has this great function. Locate file in Solution explorer. But by default it's not bound to any hotkey. Here is how you bind it.
Go to Tools -> Options -> Keyboard (Found under environment)
Or in vs2012 hit Ctrl + Q and type Keyboard and get straight to that dialog. That's a really nice new feature that let you easily find any command/setting.
You should see this dialog:
See how I started type Locate and found that VSCommand. Next step put focus on "Press shortcut keys:" and press whatever combination you want. I chose Alt + L because it fits with locate and it's free. If there was any conflicts you would see that in the last row.
Make sure you assign this key to global as you always want it to work. REMEMBER press Assign and not just OK.
Now I can locate the file I'm currently looking at my just pressing Alt + L.