[Oni]

Baccano and Samurai Champloo are some of my favorites too.

A few I didn't see mentioned, but I'd recommend:

• Black Lagoon
  
• Rurouni Kenshin
  
• Fate/stay night: UBW
  
• Fate/Zero
  
• Great Teacher Onizuka
  
• Trigun
  
• Gungrave
  
• Full Metal Panic
  
• Summer Wars
  
• Paprika
  
• Akira
  
• Berserk
  

I might make a "Top XX" list later.

I've never watched the anime for it, but I remember the first few episodes of the live action we had a watch party for years ago being good. I ought to give the anime a try.

Which show? Rurouni Kenshin or GTO?