People love retro weddings because they allow you to have fun with the fashions of the past and stand out from the crowd. The word retro is actually from the Latin word for "backwards" or "behind", so you can interpret it to mean just about any kind of style you want that's from more than 15 or 20 years ago, depending on just how vintage you want your wedding theme to be, but when people talk about retro, they usually mean from the 1950s to the '80s.
If you're going to have a retro wedding, then of course you need wedding favours to match. A bag of sugared almonds just won't stand out among your vintage crockery!
Shake it like a Polaroid picture
Why not have old Polaroid cameras on each table, loaded with film? Guests can take pics when they're at the table with instant results and either keep them as mementos from your wedding or post them into a special retro letterbox you've set up for the purpose. There's still something fun about taking a Polaroid and frantically waving it around until it develops, and these cameras and film are available on eBay.
Visit second-hand and charity shops to look for classic books as a gift for each guest. Find a mixture of well-known classics and more obscure titles: people will have great fun swapping ones they've read at the table and they are definitely conversation-starters.
Why not give away bags of retro candy to each guest? Remember Cola Bottles, Love Hearts, Drumsticks and Foam Mushrooms? Or those papery UFOs filled with sherbet? These sweet treats will go down fantastically with your guests! Display them in striped bags tied with ribbon.
If you're having a 1950s-style wedding and have a big budget (or a small wedding), hip flasks can make a fantastic and unusual gift that people will definitely take away with them. You could even supply mini bottles of booze to match. There are some gorgeous retro hip flasks available online from websites such as Etsy or eBay, or you can scour your local car-boot sales or second-hand stores.
Okay, so not many people have record players anymore, but these aren't real records either. Verbatim make blank, rewritable CDs that look like old vinyl records; fill them with tracks from your wedding to create a mix tape of memories for guests to take away and relive their best dance-floor moments with.