I bought one yesterday, I wasn't convinced it would do anything but I'm actually quite impressed!
I used it before and after putting on mascara and the results are definitely better than a traditional eyelash curler, which I tend to be disappointed with.
It's like this Sephora one and it takes a AAA battery.
I wouldn't say it was a curler per se, it's more that it lifts the lashes from the root which makes them stand out more against your eyes, rather than them pointing forwards (which mine tend to).
It was from Poundland.
No I don't work for them 