I'm a big fan of Hellovon's artwork.  I actually just bought a print a few months ago.  Gorgeous sketches.

Hellovon has a new project entitled Migration.  It is a two part project, picturing birds migrating from London to New York.  The birds are shown on two large billboards.  One is currently up in London's Brick Lane.  The second will be posted in Williamsburg, Brooklyn in the coming weeks.