I always didn't like Object Explorer in SQL Server Management Studio, primary because it doesn't have easy filtering for objects. It has build in filter, but it takes to many click to use it. This filter only lets you search across one database, and only for one kind of thing at a time (table, stored procedure, view etc). I was looking for something like Toad for SQL Server has.
Even SQL Server Management Studio 2008 doesn't have it. Finally I found
The Black Art of Writing a SQL Server Management Studio 2005 Add-In article. Joseph Cooney wrote addin that does exactly what I want. Here the screenshot from his site.

His addin has a few bugs, but still it's very useful.
One of most singnificant that before first use you need to press New Query, other wise Add-in won't be able to initialize and you face:
"When ran search windows appears, but can not type anything. After that can not focus on search text box".
However, I didn't close my SQL Server Management Studio for a weeks, so this is not a problem for me.
He also didn't provide version for SQL Server Management Studio Express and SQL Server Management Studio 2008.
So, I took his code, tweak it a little bit and here it is:
I recently found out that Stefan from iucon GmbH created codeplex project based on Joseph Cooney addin. He created two versions of it for SSMS 2005 and 2008. Also he added some new features to the addin, such as search in selection. Project can be found at SSMS 2008 Addin - QuickFind CodePlex project