Can't see any objects anymore I went to hit Numpad 5 to switch out of perspective mode but I accidentally hit another key. Now my scene looks like this:



All of the meshes are still there:

 

What can I do? I can upload the .blend if needed.
Thanks to Polosson's help I discovererd that I was on a different layer.
For others with this problem make sure your layers looks like this



And not something like