Puzzle Puzzle

Design a puzzle, consisting of: 
• a small number (<10) of polyomino pieces of varied configurations, but the same unit size.
• a rectangular container of arbitrary height and width, ideally but not necessarily integral multiples of the polyomino unit size.

Having a single unique solution:
• where all pieces fit flat within the container.
• where all pieces are placed non-orthogonally wrt the container.

Ideally / Bonus Points
• Pieces are unique
• Pieces are placed non-orthogonally wrt other pieces

References:
Polyominos - https://en.wikipedia.org/wiki/Polyomino
Four T Puzzle - http://www.cs.brandeis.edu/~storer/JimPuzzles/PACK/FourTPuzzle/FourTPuzzleSolved.jpg