Many of my brides ask me for advice on favors. I highly suggest edible favors! They will likely be gobbled up by the end of the reception! Unfortunately, with things like personalized salt shakers or candles, people tend to leave them at their seats, and money is wasted.
I especially love candy buffets (if it is in your budget), but things like little bags of chocolates will do the trick too, and don't cost too much!