When brewing up a batch of Dogfish (or any beer for that matter), the malted barley is mixed with water and boiled (this is the simplified version, people). During the boil hops are added to the kettle. The hops are usually added two or three times during the boil. Hops added at the beginning of the boil are referred to as the bittering hops and add the bitter character to the beer. Hops added toward the end of the boil are the flavor and aroma additions and bring the beer it's hop flavor and aroma. Here at Dogfish, we kinda took an off-centered approach the whole hop addition concept. We were sitting around one day wondering what would happen if you added the hops continually throughout the whole boil of the beer? Whoa ... Dude ...
We did some experimenting and some taste-testing (by far, the best part of our jobs!) and came up with a continual hopping regimen. We McGuyver-ed an old-fashioned football game (the kind that vibrated) to slowly, but surely dump the pellets into the beer during the length entire boil - we really liked the result and the 60 Minute IPA  was born (the boil time for that beer is ... ta-da ... 60 minutes long)! We feel the beer retains the best of the hops flavor and aroma without a hop-wallop in-your-face assault.
The football game didn't last too long (it got wet), so we built Sir Hops Alot (a machine we invented that perfected the continual hop regimen) for our 50-bbl brewhouse. When we upgraded to our 100-bbl brewhouse, Sir Hops Alot was retired and we brought in our latest invention Sofa King Hoppy (a bigger, badder invention that allows for continual hopping).
The continual hopping regimen was a hit and we expanded the technology to our 90 Minute IPA  (a 90 minute boil ... more time, more hops!) and our 120 Minute IPA  (I think you get it by now ... 120 minute boil ... lots more time, lots more hops - holy hops, this one is for the hard-core hophead).
Glad you asked? That's why we ask hopheads ... Feel the burn? That's the sickness and the cure. Enjoy!