I used the Porom pattern from Jared Flood of Brooklyn Tweed. It was a lovely, easy pattern to follow, and the schematics for the pattern are the best I've ever seen. I'm feeling rather chuffed with my lovely new lacey beret, I must say.
And it matches my coat. Heaven!
Pattern - Porom by Brooklyn Tweed
Yarn - 2 balls of Debbie Bliss Rialto DK in colourway 23045, from Woolarium
Needles - 4mm and 5mm circulars (I used my longest circulars, and did the magic loop method, rather than using dpns)