Lighting a drink on fire really can improve the taste. No fooling.
Admittedly, most flaming drinks have probably been dreamt up because lighting a drink on fire is cool. But seriously, kids, don't play with fire - trying to mix several flaming drinks at once is a real recipe for disaster. And please, don't do this after you've been drinking - guests prefer not to be lit on fire. Also, don't drink anything while it's still on fire. Some things aren't even funny once.
Most folks these days are only drinking flaming shots - but you can make almost any drink flame if you first heat the liquor in a spoon. If you hold the spoon steady, the vaporized alcohol should collect above the spoon, allowing you to light the alcohol fumes. Then, you can carefully pour the flaming alcohol over the prepared recipe. Despite your desire to see the alcohol light, do not peer closely at the drink or at the spoon - if the flame is too pale to see, turn the lights off. Don't light your eyebrows on fire.
Never leave warm alcohol unattended. Always close bottles of alcohol before lighting anything. Do not keep warm alcohol where it can be a danger to yourself or guests. Never add spirits to something on fire. Please do not light drinks at a gas station, chemical plant, or in a crowded theater.