Don’t worry, they all did quite well for themselves financially.
It is a shame that Gingrich got the boot so early , the members the GOP Caucus must have really hated him.
If I'm not mistaken, I believe Gingrich resigned -- not under pressure, but because he was vulnerable to the revelation of an office romance. Not good form when you're leading the prosecution against a perjured President who was involved in an office romance.
Nonetheless, Newt may not have been terribly popular as a Speaker -- as opposed to his obvious popularity as a Minority Leader. Tom DeLay, for example, described Newt's management style as being dilletantish -- focused on a distant vision, constantly changing goals...and a lack of interest in the nuts and bolts of legislating.
Newt is, after all, a professor of history. Well-suited to lead a revolution but, perhaps, not fit to administer a victory.
We all know people like that -- for example, entrepreneurs who build businesses...then, once the business is mature, lose interest in the day-to-day administration (and really aren't very good at it).