In the search for yarn that's (a) cheap (b) soft (c) wears well, I recalled the Patons Smoothie DK that I remembered doing a baby jumper in. Turns out the only reason it didn't pill was that baby grew out of it before it had been washed too much. This jumper in the same yarn pilled pretty much straight away. Boo hoo.
See my ravelry notes here, the pattern is the child's placket neck pullover, changed to be knitted top-down (instead of bottom up) and with a stripe pattern and colour based on someone else's project knitted to a different sweater pattern.
I should always do a tension swatch and this jumper is why. Gah. At least