Loads of Lucario's
Level 100 Grounden is top of the heap though I think it's legendary and also level 100.
A shiny Tentacruel also
Many good IV pokemon babies
I try to give back sending out Y exclusive Pokemon and sent out my LVL 100 Weezing the other day and good bred Pokemon.
I sent out Litwick last night and two hours later I got it back lol, always funny when that happens. I wonder trade non-stop every 100 or so you can expect something really good, and every 50 something rare.