Past the beautifully groomed pompadour of the Harvard & Stone doorman, beyond the tractor-seat barstools and chicken-feeder light fixtures is the back bar at this World War II–style watering hole in East Hollywood. Dubbed R&D, or "research and development," this is an active cocktail test kitchen where the bar menu changes every night with guest mixologists on site. The venerable Pablo Moix has doused customers with tiki drinks, Alex Straus of the Bon Vivants has experimented with French liqueurs, and in-house bartender Mia Sarazen has presented whiskey creations that may or may not grow hair on your chest. Although the intimate cocktail space leans toward culinary creations, R&D does get funky. One regular still talks about the bar's onetime Brass Monkey; that's Olde English malt liquor mixed with orange juice — yes, the one from your formative drinking years. Now that's worth a toast. 5221 Hollywood Blvd., E. Hlywd.; (323) 466-6063, harvardandstone.com.