Try a tank or tee knitting pattern! Knitting a sweater doesn't have to be a huge commitment. Knit a tank top, tee or shell - it will be completed before you know it and you'll have a great sense of gratification for completing a project. Not to mention, you'll end up with a sweater that's a great layering piece.
There are many styles of tanks and tees to suit your style: Rib knit tanks, lace shells, cabled tees, and knit camisoles. Wear these tanks alone or use them as a layering piece, the choice is up to you!