Try "Save the Sheriff" at miniclip.com, a Shockwave game. It's not really representative of the great things Shockwave can do, but it's cute and well made.
Otherwise, I think your best bet for nice-looking platformers would be to get a new console or hand-held.
People don't play 2D games today because they think it's boring, which is wrong.
What's boring is yet another first person shooter with a billion polygons made to look like concrete and rusty metal and crates and other inspiring constructions... they all look the same and you do the same things in every one of them, but they sell by the cartload. Oh well.