Stylish Secret :: Name Tag Place Cards
Here's a super simple and fun way to designate seats (and keep track of drinks): Use name tag place cards on your glasses. They're inexpensive and easy to remove from your glasses. These tags can also be used to label party favors, or to label beverages on a bar (I like to put mixers in glass bottles instead of their original packaging and labeling the bottles keeps things clear).
Use the Etch-it labels, pictured above - they work like a chalk board, and you use your nail or a pen instead of chalk to write the names - or any other name tag label, though they might not be quite as easy to remove as the Etch-it labels, which are specifically made to be removable from glassware.
The Etch-it labels are sold in packages of 15 and cost $3-4 per package.
Birthday Express - $2.99/ package
Shindigz Party Supplies - $3.99/ package