This is Rosey Posey. She is a G3 pony I found at a thrift store for $2 with a value of $250+. Her story is pretty interesting. She was released at a limited charity ball for the Hasbro Children's Hospital; the tickets started at $75 (I think) and she was offered as a gift only at the event. This means that probably less than a thousand were ever made, so it's pretty cool that it's possible for very rare ponies to be found at thrifts!
The image is large so I put it in a spoiler.
- Spoiler: show