This isn't the first inquiry we've had along these lines. Back on Jan. 24, 2006, the subject of QoD was whether or not it was legal and/or logistically possible for a reader to scatter their friend's cremated remains on the Las Vegas Strip. The bottom line in that instance was "no," at least to the legality aspect, but we did share some creative ways to respect the wishes of this particular deceased fan of Sin City. Check out the QoD archives for more information.
As far as your query is concerned, a brick at the Flamingo might well be a good route to take, especially if your friend had any affinity with that particular property. The bricks, which are laid in the Flamingo Gardens, are still available for purchase at a cost of $150 each, which includes up to three lines of engraving. Click here to download the commemorative brick order form.
The light-bulb idea is a good one, too, but we don't think that it will work in this particular instance. The way that this souvenir program operates is that you can purchase a light bulb that's authenticated as having come from the famous Welcome to Fabulous Las Vegas sign, even specifying from an online calendar the date that you'd like the bulb to have come from and from which "slot" position in the sign. However, once you've purchased a bulb, which are $69 each, it's boxed and shipped to you, along with a certificate of authentication. We placed an inquiry to see if it's possible to purchase a bulb and leave it in the sign in perpetuity, but we have yet to hear a response back from Las Vegas Lights and suspect the answer is "no," since it would be hard for them to administer and it would diminish their ongoing business potential if bulbs could be bought outright, rather than being replaced and resold.
One final suggestion is to plant a memorial tree for your friend, or have one planted for you. With prices starting at $29.95 for one tree, memorialtrees.com will plant a tree to commemorate your loved one, or you can plant one yourself. If you go the latter route, there's some bureaucracy involved. First, pick a tree that can withstand the extremes of the Las Vegas climate, and make sure you know how big it will get when you're looking for a suitable spot to plant it. You'll need to contact the City of Las Vegas Planning and Development Department to make sure the area is zoned for planting trees and you need to go through the Las Vegas Parks and Recreation Department if you want the memorial tree to be planted in a Las Vegas park.