
Originally Posted by
Owlie
If you get lucky, there are some sweaters (even store-bought) where the fabric isn't knit, cut and sewn, but it's knit so that the body up to the sleeves is a single length of yarn. You can take the sweater apart, unravel it, and use the yarn for your own nefarious purposes.

Or take 100% wool sweaters, wash and dry them in the machine (exactly what you should NOT do with wool sweaters!) so they shrink and felt, then cut out mitten-shaped pieces and sew them together. There are patterns that put the thumb in a better spot by using separate thumb pieces sewn onto the main part, to avoid the awkwardness of having the thumb out to the side, but they are also more complicated.
2011 Surly LHT
1995 Trek 830