Anheuser-Busch is launching its caffeinated beer in the UK. BE (Beer With Extra) contains 5% alcohol, 60.4mg of caffeine, guarana, and ginseng. In the US, BE is sold as B-to-the-E (BE). My sister-in-law Heather Sparks points out that there's also a caffeinated and taurine-laden malt liquor on sale in the US called Sparks (no relation). From the BBC:
Victoria Manning, research psychologist for Action on Addiction, added: "(The introduction of BE) concerns us because the combination of caffeine and beer will enable people to drink more because the caffeine will keep them awake longer."
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UPDATE: Liquid Charge is yet another caffeinated malternative beverage. (Thanks, Jackson Jeyanayagam) And here's an article from Beverage Business that mentions a few more.