Summer Glau (River) from Firefly/Serenity will be appearing at the Wizard World convention in Arlington, Texas at the Arlington Convention Center on November 4-6. Also appearing are Ron Perlman (Hellboy) and Sean Astin from Lord of the Rings. A ton of others are scheduled to appear as well.
Here's the link to the convention site, and a schedule of events. The tickets are running anywhere from $20 for one day all the way up to a special Wizard's pass that gives you access to all kind of secret special events.

For those of you who live in DFW, the convention is located a couple blocks south of I-30 on Ballpark Way.

http://www.wizarduniverse.com/conventions/
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