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(photo from Martha Stewart)

If you do not have Adobe Reader yet, you can download it for free here.

Petal Favor Box

Cube Favor Box

Trapeze Box

Cake Box

Pyramid Box

Hexagonal Box

Matchbook Box

Takeout Box

Milk Carton Box

and lots more here and here.

You can buy bulk card stock for reasonable prices from places like Anchor Paper or Discount Cardstock. It may not be the most cost effective route, but you can create your own favor packaging to match your colors and style.