Yes, I'm sure El Rastro is open, even on Easter Sunday.

What's the best thing I've ever bought there? I don't think I've ever bought anything there but did enjoy browsing. Some say that El Rastro is losing its original charm, that more and more of the merchandise is the same as that you'd get at any "Chinese store". Others say the stuff sold at El Rastro is just junk. But as steve robinson says, old postcards and posters are some of the most interesting things for sale there. You can also get decent new leather bags for cheap-ish, old peseta coins, as well as antiques at varied quality.

I really need to go back, with wallet totally secure, to check out what they have these days. It's been more than 3 years since I've walked those streets on a Sunday morning. The best part are the neighborhood tapas and drinks at mid-day. Those bars are packed!!

Saludos, MadridMan