I just posted this in another thread, but I have completely fallen in love with my Hai Straightener. I have the Stik, and it's very small, and shaped like a curling iron, so you can actually straighten your hair, or curl it.
It also heats up instantly. Honestly, you plug it in, and 10 secs later, it's ready and hot enough to straighten your hair.
It's so great. I finally ordered one online after my stylist used it on my hair a couple times and I loved how soft and shiny it was.
It is a little more expensive than some of the drugstore brands (about 75$) but it works like nothing I have ever used before -- AND it's a curling iron. I love it.