B&H Photo-Video offers the Canon Speedlite 270EX Flash, model no. 3806B002, for $129 with free shipping. (Adorama Camera via Amazon charges the same.) That's the lowest total price we could find by $20. Features include a built-in AF-assist beam, 2-step coverage for 28mm and 50mm focal lengths, bounce function, optimized recycling time, and more. It's compatible with Canon EOS-1D/s Mark II, Mark III, D-20, Elan 7N/E, or newer models.