If you travel more than a couple of times a year, you should be a onebag traveller with no check in luggage. There are times when you need to check a bag in and this where the CalypsoTag comes in handy (link).
The distinctive tag comes in 4 highly visible colors.
Add one to your luggage to quickly see it come down the conveyor belt. The Calypsotag has another trick up its sleeve: it comes bearing bluetooth 4.0 goodness. With their app, your phone will notify you as your luggage get's closer. This means you don't have to stand by the conveyor belt waiting, in a crows of tired and angry travellers. You can stand a couple of feet away and relax. Your phone beeps, you move closer, pick up you luggage and walk away.
Most other bag trackers offer more detailed global positioning information of your luggage but cost $10-15 a month for global GSM cell service.
All of this CalypsoTag can be had for a reasonable $99 one-time fee.