If I have yummy, fresh, wild Pacific salmon, I just roast it in butter (basically, what you do with the lemon slices), and serve with lemon wedges. It's the best way, in my opinion.
If I have salmon that has been frozen, etc. I really love sorrel sauce, it goes so well with the fish. Here's a recipe:
http://www.theheartofnewengland.com/...monSorrel.html
Sorrel is a bit hard to find, but I've started growing it because it's a perennial herb. DS loves to eat it straight out of the garden!