I saw Troy a few days ago and was kind of glad slings weren't in it. It might have tainted their image being in such a poor film.
In the original text of the Iliad, it does mention slings. I've searched this document and pulled out matches:
http://darkwing.uoregon.edu/~joelja/iliad.html"the spear went right through his
hand and stuck in the bow itself, so that to his life he retreated
under cover of his men, with his hand dragging by his side- for the
spear weighed it down till Agenor drew it out and bound the hand
carefully up in a
woollen sling which his esquire had with him."
"but they had come to Troy armed
with bows, and with
slings of twisted wool from which they showered
their missiles to break the ranks of the Trojans."
Thats it, out of the entire epic poem.
Chris