Trinity force is an interesting item.
The icon shows that it's combined by 3 swords, a pair of Zeal and Sheen, but where's the Phage?!

The truth is: you spend 300 gold for sticking them together.
It's a WINDMILL!

Phage is the central axis of Trinity Force
The yellow blades are Zeal, and Sheen is the blue one.

https://www.facebook.com/photo.php?f...type=1&theater (It's not my Facebook album)

If someone doesn't get the point, here's the 3-D diagram.
http://ppt.cc/JeVN

Then...how does Irelia to use it?
http://truth.bahamut.com.tw/s01/2012...b979c8226a.JPG
(This picture is drawn by 冷蛙鍋, a illustrator from Taiwan. He posts his arts at http://home.gamer.com.tw/creation.php?owner=lcomicer)

It SPINS!

Edit: Just as Maha said, it can be used as a propeller which makes you move swiftly!

PS: I don't own any pictures above or following, but they consented me to put them here.
Edit: Moar Trinity diagram!
Trinity for Ashe :http://ppt.cc/2GRo .. it works like how it looks
for Ezreal: http://truth.bahamut.com.tw/s01/2012...0248b63d2c.JPG (also by 冷蛙鍋)
for Shen: http://truth.bahamut.com.tw/s01/2012...0985cf33f6.JPG (by ltjay17 )
for Stanley: http://ppt.cc/ZbSj (by nichaellin)

Should I make the loooong link shorter or leave it alone?

Attached Thumbnails

     

Mind is slightly blown.

soooo...pinwheel of doom?

Garen 2.0 with 2 axis of spin, horizontal and vertical. Shredder of doom

Inb4 they actually figure out how 2 books = gun.

[b][b][o][[o][k]
[o]
[o]
[k]

close enough

book gun.

The books are actually chapters of the Book of Armaments.