First add-on's I remember buying were for games like Baldur's Gate 1 and 2, Morrowind and Gothic 2. They all seem like part of those games now and it's hard to think of playing without them. The first actual DLC I remember actually downloading from the internet was St. Patricks Day Annah for Planescape Torment. Morrowind also had some free DLC content I remember enjoying. My favorites would probably be from Bethesda titles. They added a lot of hours of fun with their DLC for their Fallout and TES games. However, the most I've spent money on is definitely the Sims franchise as I've bought every single expansion for every single Sims game. I've spent over thousands on one stupid franchise throughout the years. Probably would make me very sad if I added it all up.