We've just launched! Some things are still being worked on, so excuse us if you see a bug or two -)
HDR images show greater range of tonal detail, than your camera could capture. This site emulates HDR effect so you can play with it with no Photoshop or other software. You can enhance some pictures really well and produce stunning results.
It's up to you to experiment now, and don't forget to share your best results and give us your suggestions.
Good luck! Read Help if you have questions.