Various accents (Scottish, English, Irish, North American, French, German, Spanish, Belgian, Australian, Indian, etc)
I've performed impressions of a number of characters:
Yami/Atem from the Yu-Gi-Oh! franchise
Jack Atlas from the Yu-Gi-Oh! 5D's Anime Series
Chancelleor Palpatine from the Star Wars franchise
Oliver Queen/ Green Arrow and Slade Wilson / Deathstroke from the Arrow TV series
Azazel and Detective Pete Sheridan from the Supernatural TV series
Baron Von Strucker and Tony Stark / Iron Man from the Marvel franchise
Daryl Dixon from the Walking Dead TV series
Bruce Wayne from the DC Comics franchise
T.K. from the Angel Beats Anime Series
Suaku Kururugi from the Code Geass Anime Series
I've also voiced for original characters:
The Agreeable Snowman and Garden Defense Gnome for a Christmas-themed Mod of the Hearthstone mobile game.
The Admiral from an original audiobook set in the Star Wars universe.
Looker from an Youtube video spoof of the Pokemon franchise and the Ace Attorney video games.