Put the shrimp, garlic, parsley, Old Bay and beer into a pot, give it all a stir and bring it to a boil over high heat.
Let the shrimp simmer until they are opaque (about 2 minutes) and then scoop them out onto a platter or bowls to cool off a little.
While the shrimp are cooling, make the dipping sauce by stirring together the melted butter, lemon juice and Worcestershire sauce. Divide the sauce into individual containers (I like to use tiny prep bowls for this).
Serve up the shrimp in the shell, letting people peel their own. Put a bowl in the middle of the table so folks have a place to toss the shells, and instead of napkins, hand out individual wet washcloths for their hands.