I have a friend living on Vancouver Island, a place cold and damp through the winter, and for Christmas I thought she'd like a lovely, cosy felted-wool cover for her hot water bottle. Time is ticking away, and rather than knitting and felting one, I thought I'd maybe find a thrift-store wool turtleneck and start there.
The first thrift-store I went to I found this:

Beautiful pale grey and thick, but wait it's not just wool:

That's right, 100% cashmere. And thick and heavy too:

Wow! That's quite the find.
Yes, I know.
So I threw it in the washing machine. On hot. Twice.

Now it's the right size:

For all you non-knitters out there, once a woolen garment has been felted, the fibres fuse together and it can be cut and sewn just like fabric:

I shaped the bottom a bit, leaving enough to fold over at the back:

Then, with some matching thread:

whip stitched the edges closed:

I added some decorative blanket stitch in black silk yarn around the edges, using an embroidery reference book (because I'm hopeless at embroidery):

And I added a mother-of-pearl button to close it at the back:

And a little bit of needle felting for the front:

So it's all hers:

This entire process took a morning, and I'm feeling pretty pleased.