As a wedding photographer who has photographed everything from solemn church weddings to candle lit ceremonies in small halls to large outdoor venues, I have heard many different types of wedding vows.
I personally suggest having vows that reflect the type of ceremony you are having. If you are modeling your wedding after the royal wedding, then write your vows to reflect that. A rock star wedding on the beach with a trash the dress session scheduled for the next day should adress that unique ceremony as well.
I'm of the belief that having "fun wedding vows" doesn't make you any less elegant, just as traditional vows do not make you any less fun. These are all just my opinions as I'm just the photographer. Please consult with your family and your officiator for best practices.
I would like to point you to a few sites and articles that may help you with your wedding vows. For many different styles (along with user ratings), check out My Wedding Vows.
For an in depth article, visit The Knot's 20 Tips For Writing Your Own Wedding Vows.
To find some really elegant vows, visit Elegant Vows. This site has paid and free vows available for you to use.
For a lighthearted gesture of love to your spouse on your wedding day, check out the Wedding Vows Den.
As wedding season approaches (my first assignments are in April), I hope you find this post useful. I look forward to hearing your vows - rock star or traditional - as I photograph your ceremony this year!!