Leprechauns in 3.5

[Dr.Epic]

I was wondering do leprechauns exist in any source material in D&D 3.5? I have an idea for a quest about a psychotic, killer leprechaun. I'm pretty sure that's never been done.

[some guy]

Use redcaps, they're psychotic killer fey who look like small wrinkled, old men who dip their hats in the blood of their victims.

Edit: can't remember the source, probably MM3 or MM4.
Edit the second: they have also nice fluff, but that can be changed up to the DM's whim.
I have a simple and short one shot scenario using a redcap which I submitted for Zak Smith's SAGE request. It can be found on his blog, Playing DnD with Pornstars, but I'm not sure if I can link to his blog on this site (it's really just about DnD, but I'd rather err on the safe side).

[joe]

For leprechauns, I generally use gnome spellcasters and give them leprechaun themed spells (invisibility, teleport, glitterdust, faerie fire, prismatic x, etc.) Sorcerors, Bards, and Beguilers would be my immediate choices.

My current campaign's BBEG is a psychotic killer leprechaun named Oscar.

[PairO'Dice Lost]

I kind of split the difference between joe and some guy--I take redcaps as a base, remove the whole blood cap aspect, and replace it with the ability to use ventriloquism, invisibility, and minor image at will, plus the ability to fabricate anything out of false gold that lasts until the next sunrise.

[HunterOfJello]

Unseelie Fey template added to your choice of Halfling or Gnome variant.

[El Dorado]

Obligatory Lucky Charms comment.

[Thurbane]

You can find a user made 3.X Leprechaun at the Enworld Creature Catalogue.