Spices are definitely a favor that will have a spot in every guest's pantry. We also love the idea of letting guests choose sweet or spicy! Buy them in bulk for cheap at international food stores, bargain stores like Walmart, or the dollar store. Store them in Mini Glass Bottles With Cork Stoppers ($14 for 24).
If you don't feel like making them yourself, you can these already-made Mini Spice Jars ($48 for 30) for a little more money.