I have recently had some fun at the expense of the poor sackbut. (See Instruments With Funny Names) My conscience has been reproaching me ever since. I hope that I haven't offended any sackbut players. I expect that most sackbut players have a good sense of humor and aren't easily offended. At least, I hope that's the case.
Actually, the sackbut is respectable instrument that played an important role in the history of western music. Basically, it's name comes from Middle French and means push and pull (from sacquer and bouter). The name makes sense when you consider that the sackbut is an ancestor of the modern trombone.
The sackbut was developed from the medieval slide trumpet. The slide trumpet was quite a popular instrument in its day, but it had the disadvantage of only having one slide. You had to move almost the entire instrument to change the note. The double slide of the sackbut solved this problem. Like the trombone, you only have to move the slide to change notes.
We tend to associate the modern trombone with comedic sound effects, but the sackbut played an important and dignified role in church music, even in grand cathedrals. It had a pleasant vocal quality and was prized as an accompaniment for choirs.
Eventually, the sackbut went into decline and became nearly extinct. However, the trombone became a popular instrument. Because there's increasing interest in authentic performances on period instruments, some trombonists are taking up the sackbut, leading to a small resurgence of the instrument.
Sackbut Links
The Sackbut at The British Trombone Society
Wikipedia Article
Sackbut Video