I have a feature suggestion I would like to put out there.
I think it would be very helpful to add some sort of dropdown menu next to the search box at the top. It could list something like "Stack Overflow" , "Meta", "Server Fault", "Super User", "My Questions"
Then you could pick 1 and type in your search query and it will pass it on to the appropriate site, it would integrate the "Family" of sites a lot better. Obviously if you were on stackoverflow and you picked to search serverfault, it would not load the resuls on SO but would redirect you to serverfault or possibly open a new window.
This could then have a simple option to search your own questions because typing in user:745 [php] or user:me [php] it could populate the search box with that for you already (often I have to come to Meta and search for how to find my questions because I forget the syntax sometimes.
Just my thoughts
Here is a screenshot of how myspace does it... alt text http://img2.pict.com/69/0d/97/2565293/0/screenshot2b202.png alt text http://img2.pict.com/98/f1/4a/2565295/0/screenshot2b203.png