Not much but here goes:

Visual interior mods: StarTech shift ****, SRT6 emblem (from rear decklid) now on centerstack (dash)
Visual exterior mods: Debadged, Andrew's Crossfire emblems, Exposed chrome lugbolts with Mercedes center caps, Eibach pro kit.
Visual engine mods: n/a
Performance mods: ? K&N filters
Wheel/tire/brake mods: Stock for now. Will change to Rotex pads soon.
Electronic mods:
Misc mods: About 10 coats of wax since I bought it in 03/07.
Future mods: Bought difusers a few months ago but have not put on yet. May paint them first.