Have you been on the wedding blog Once Wed? If you haven't you should it's great. I've been a regular visitor for quite some time and it is there that I came across the idea of giving jam or honey as a wedding favour. I really love this idea as I love jam and honey and I also like the idea that you can make it yourself (not that I ever have made jam.... I'll give it a go though and if it fails i'll order some)
You can also jazzy it up with a small piece of fabric and ribbon and put a personalised label on them. All images used here are from Once wed's wedding ideas section link here. They have some other great favours as well.
My favourite favour I received at a wedding was from my friend Kirra. Her and her husband gave everyone a rosemary plant. She had wrapped the pot in hessian and tied it with ribbon. What a great idea.
My friend Kelly recently did a post on her blog about gifts in jars. Check it out here