The first place to start would be with your stationary: save the dates, invitations and subsequent RSVPs, ceremony programs, reception menus, and thank you cards. Many companies will help you design a monogram and you can order whatever you need through them, or for those DIY brides you can have a rubber stamp made and you can use it yourself.
Receptions offer a myriad of additional possibilities. You can put your monogram on your table and place cards, or even create something to use as a napkin ring. Hanging tags can be made to put on guest favors or around a bottle of wine, or - for the couple who really want a special touch - you can personalize an actual bottle of wine! Even dance floors can be dressed up with projection lighting or stick-on decals.
Another outlet for your monogram creativity is in the realm of apparel. You can always have his and hers shirts made for either the bride-/groom-to-be or as newlyweds. Designed can be screen printed or even created with rhinestones. Monograms can also be put on tote bags for gifts to your wedding party or welcome bags in the hotel rooms of out-of-town guests. Marrymonograms.com will also customize a special clutch for the bride or to give as gifts to the bridesmaids.
Now for my very favorite idea. Marrymonograms now offeres customized flowers. That's right, flowers! They can monogram roses, calla lilies, tulips, or rose petals in most colors and ship them overnight directly to you or your floral designer from California. At just $5 per stem they are only $2 or less than roses from most florists. It may be a little overwhelming for an entire bouquet or centerpiece, but it would be a special touch to add one or two in an arrangement. Just think how surprised your guests will be when they notice just a subtle and personal touch.
As with all aspects of your wedding planning, have fun and don't be afraid to get creative!