My parents 50th anniversary is coming up. One of the things I thought I'd do was route them a custom name/house-number sign for their winter AZ retirement home. I'm OK on the actual sign making part, but have a goofy idea for after routing the lettering. I'm wondering if there's some kind of glow-in-the-dark compound or something I could mix in with a compound that I could fill the lettering channels with?? I'd like something that would flouresce when hit by car headlights or landscape lighting. I realize I could probably just get some flourescent paint and coat the lettering channels. But I was wondering if I could find something to actually fill the channel and bring the lettering back flush with the surface. Maybe this isn't feasible from the standpoint of finding something that wouldn't shrink and crack in the channels or expand/contract with the wood. Like I said - it's a goofy idea. Just wondering if anyone here had any thoughts.