when I got my engagement ring, Steve (him indoors) got a titanium band and wears that on his wedding finger. He's not really a jewellery type of guy, but wanted something to mark the event, so we plumped for this as it's matt finish (not too bling for him) and very light/comfy to wear. If we ever get round to getting married, he'll just swap it onto his right hand and wear a wedding band on his left.
When I met my husband in 1992, we new instantly that we wanted to be together. We went to Kefalonia 11 weeks after we met for my husbands 30th birthday and I bought him a plain gold signet ring. On the morning of his birthday, he proposed, I said yes and when he opened his present he asked if he could wear the ring as an engagement ring - which he did. When we married 11 months later, he moved the engagement ring to his right hand so he could wear a plain gold wedding band. (We have been married 11 years tomorrow).