Logic Masters Deutschland e.V.

This was heavily inspired by kolot's wonderful and monstrous Region Geometry.

Rules:
Normal sudoku rules apply, the regions are to be deduced. A few region boundaries have been given.
Clues outside the grid are all both Y-sums and skyscrapers sums.
Y-sums: the first Y digits from the side of the clue sum up to the clue value, where Y is the Xth digit in the corresponding direction, and X is the first digit in the corresponding direction (seen from the side of the clue). The first Y cells are also all in the same region, and the next cell is in a different region.
Skyscrapers sums: every digit along the row/column represents the height of a building. The clue value equals the sum of all digits/buildings seen from the side of the clue, where higher buildings block the view of lower buildings. Every seen skyscraper (in rows/columns with clues, seen from the side of the clue) is in a different region.
Along the thermometer digits increase from the bulb end.
Cages each stay entirely within one region.

Try it here.