What's that and why's there a hole?
 

Today looking at the engine and stuff under the bonnet I saw this little reservoir like thing and it has a hole in it (and some rust stains that soon might to be holes as well).

Can somebody tell me what this is? Should I be concerned about the little hole? Have it checked out (certainly not by the dealer though; they had my car for a week because of a whining noise I kept hearing and they couldn't find anything wrong)? Thanks.
http://farm5.static.flickr.com/4120/...6b1a4ed0_b.jpg
http://farm5.static.flickr.com/4098/...392c2b8c_b.jpg

That's your engine mount. Don't worry about it.

I just checked mine (just replaced recently so it's still clean) and the hole on the left is a tear drop shaped hole (vent hole?) that is part of the mount; the one on the right must be a rust hole as mine doesn't have it.

Whew! Thanks guys.

I'd keep an eye on that rust though. Those damn mounts are known to fail. I had mine replaced not too long ago.