These make total sense, since your guests will still know where their calendars are eight months after receiving your save-the-date. This can't always be said about the save-the-date itself...
Rows of Prose
I love the idea of tying the ceremony programs to the chairs with ribbon. The outer envelope possibilities are endless... How about printing a fun fact about the couple on each envelope, or the lyrics to a meaningful song? How about a quote about love, or a poem? Or vows? (See what I mean?!)
Watch and Weep
I don't know if I'd actually do this for my own wedding (is it conceited to assume people will cry at your wedding?), but I still think these are so cute: Tissues built in to the ceremony program. And it would be so incredibly simple to DIY... you'd just need a travel pack of Kleenex and some 4-bar envelopes.
Pencil Me In
How awesome is this?! Black craft paper rolled out across each table, with the place settings written in chalk. This would be great for a low-key affair, or for a messy meal. It can always be removed right after the meal, making for a clean slate for dessert. It would also be fun to place glass jars full of chalk on each table, so guests can doodle.