I start most mornings with a quick tour of "my" SE sites. Generally I hit them in the order they appear in the footer, doing all the graduated sites I follow, then all the betas. If I have been active on a site, then I'll check there first to see if my rep has changed. And if there's an inbox notification on the first site, I'll detour over to wherever the reply is, and read that first.
No matter the order, all the sites load at about the same speed with one glaring exception: http://scifi.stackexchange.com/. When I click that link in the footer, my browser sits there "waiting for " it for a really long time. More than half the time the page loads without any CSS or whatnot:
If I then click a question link, the stuff manages to get loaded and the question looks fine, as does the main page when I return to it. A few months ago travel used to do this sometimes, but now it does not. Yet scifi continues to. Are different sites on different servers? What would cause this behaviour?