Cardistry flourishes I'm pretty good at already:

• overhand shuffle (has a false shuffle variant)
• ribbon spread [2]
• thumb fan

Flourishes that I'm working on now:

• the minimal-bending riffle shuffle, that's also nearly silent [2] [3] [4]
• Charlier cut, the simplest one-handed cut
• "fidgets":
  • Chris Ramsay — ferris, flirt, and Prince Charming [1] [2] [3]
  • Chandler Henry — thumb spin, top swivel, and quick aerial [1] [2] [3]
• the full casino shuffle [2] [3]

Flourishes I want to learn:

• Hindu shuffle (has several false shuffle variants [1] [2] [3])
• armspread
• revolution cut
• riffle shuffle
• spring

Internet resources:

• United Cardists, a forum
• /r/cardistry