This next puzzle is a little mathy in the sense that it uses the primes, but really all you need to know is that the first three prime numbers are 2, 3, and 5. Basically, if you see a number between cells then exactly one of those cells contains a prime, and that number tells you the sum. A diamond means that either neither of the numbers or both of the numbers must be prime. Other than that, the rules are identical to normal Sudoku with each number appearing exactly once in every row, column, and two-by-three cage.
For a solution, PDF, and zoomed in individual puzzles visit Quadrata at www.quadratablog.blogspot.com.
