For example, in the Tudor era, there is this entry for the job of "Groom of the Stool:"
Attention all ambitious noblemen! Following the untimely death of Sir Henry Norris, a new groom of the stool is required by Henry VIII. The primary duty of the groom is to see 'the house of easement be sweet and clear' or, more plainly, to clean the royal rear and privy.
It's always interesting to look at your own stool but imagine looking at the king's and laying it in a dish. As for wiping – with the hands: there is no toilet paper at the Tudor court – just try not to think of the meat-heavy diet of the big man.
This is a challenging position for someone looking for exciting openings, for whom no job is to too big or small. Light relief may be provided by regular enema and laxative administrations. It's a coveted position – no one else will be so often alone with His Royal Highness, so although you will be dealing with number twos, you will be number one in the privy chamber.
I'm sure many people have wondered about this particular job before...
Actually, this site has plenty of useful information about jobs in historic times. Look at the Fuller or the Tanner...and realize that the first people with these surnames did those jobs.