Well, I'm going to cheat a bit because this was me and not one of my players or DMs. I had a boring 'ol dwarven fighter, either in 2E or very early 3E. I decided he was going to be the dwarf Indiana Jones and was able to get pretty close to what I wanted mechanically. A dwarf's natural underground abilities and lore skills in ancient archeology got most of the job done, and I think I even got a whip as a weapon. I was planning to multiclass in thief, but ended up having to leave the campaign before I got very far. ( I got engaged and all of my time suddenly became allocated elsewhere.) The main RP element was that I wasn't after loot, at least not the normal kind. I was looking for knowledge and artifacts of ancient cultures. Some of it was very valuable to the right collectors, but that wasn't really the point. It also gave the DM an easy hook for adventures: my PC had located a probable archeological site of an ancient civilization and we were going to check it out.