With my wedding coming up in 2015, I am in full wedding stationary production; Save the dates, Invitations, Orders of Service, Place cards, Menus, Seating Plans, Favour boxes, and anything else I can possibly think of to make out of paper and card.
My Stationary is simple, double stamped punched heart, attached to a card with a peg (and a foam square and liquid glue) with a simple stamped title, and a printed insert.
The key to successful homemade wedding stationary is just that, keeping it simple. Depending on the number of guests you could have hundreds of each item to produce, and although in theory it is cheaper to make your own costs can quickly spiral when adding sparkly bits, ribbons, and fancy card stock.
The design also needs to be easy to mass produce, its a great activity to involve your bridesmaids in, but are they as crafty as you? No? then make sure its something they cant get wrong, or you could find yourself making everything again and the time leading up to the wedding is stressful enough without having to make hundreds of wedding favours.