Maybe a 1,000th richest, 900th, 800th, etc with a small forum title or little achievement until someone reaches the richest user?
I can dig it. "(User) is the 99%" or something as the title?

I think it would be kinda fun trying to save up
Seriously, I NEED a "-user- is the 99%" title! c:
[edit] (Editing bc something is missing o.o) I think getting a "900/800/...th richest user" is funny as a tiered achievement, so you have to carefully adjust your sP to be neither the 902th nor the 899th richest user. Besides that, I'd really like a user title with "99%" aka "ALMOST accomplished something" in my life XD
Wut??? Virtually everyone is in the 99%, there's no achievement for that. That's what 99% means. More than that, many users are casual player or log on a few times and then go away never to be seen again and their very low sP total counts for rankings and averages, so the actual wealth curve is probably pretty skewed from the normal distribution. Players who actually play can be earning themselves a pretty good amount of sP just for doing one day of quests putting them pretty close to the top in all wealth (compared to all the monies and the casual players) without even trying.
This is a weird Suggestion.
I'm sitting on a billion right now, and I'm only around rank 500 so this would be a pretty crazy hard set of tiers for users to get on their own, but this is not what happens.. Already users get together and pool sP to get Richest, so these tiers really it's not any harder so much as it is tossing a bunch of Achievements at any user going for Richest all at once.