I like chia seeds to replace eggs in flour-based stuff (baked goods, pancakes, etc.) One tablespoon of chia seeds soaked in 2 1/2 to 3 tablespoons of water for 5 minutes replaces one egg.

I started doing it for my cholesterol (chia seeds have a much better polyunsaturated fat ratio) but then I found I actually really like it. They work generally the same but add a little crunch without changing the flavour.

I'm not usually eating baked goods for the vitamins, so what I'm missing from the eggs (B12, for example) I'll get from other sources. Also, chia seeds can be kept on hand for a long time without refrigeration, so they're a good survival food :D