The maw of a sarlacc.

"In his belly, you will find a new definition of pain, as you are slowly whipped and chained digested over ten one hundred a thousand years."
―C-3PO announces the "fate" of Luke, Han, and Chewbacca[src]

A sarlacc is a giant masticating carnivorous life form that resides in pits on harsh worlds such as Tatooine. Slowly feeding on creatures, both sentient and animal, that are unfortunate enough to fall or be tossed into its maw, these...things...can exist for millennnia. Being digested by a Sarlacc REALLLLLLYYYYY sucked, because it was soooooooo painful. One sarlacc in particular gorged itself on several members of Jabba Desilijic Tiure's criminal organization in 4 ABY in the gangster's abortive attempt to execute Luke Skywalker, Han Solo, and Chewbacca.

Born without a sense of humor? We are inspired by your courageous struggle. …Just kidding. Get the hell out of here and go read Wookiepedia's "real" article on Sarlacc.

Boba Fett was one of those who fell into the Pit of Carkoon where that particular creature lived, but he was able to escape, to be rescued by Dengar and was subsequently eaten.