I'd knit a hot water bottle cover - it takes about 100g. And probably a scarf.
Hot water bottle cover
4.5mm needles
Cast on 60 stitches. Place a stitch marker at 30 stitches – the halfway point. This will make it easier to know the middle – as this cover is folded in half and seamed up at the end.
Knit 1 row
Purl 1 row
K2, make 1, knit to 3 before the stitch marker, make 1, knit 2, slip marker, k2, make 1, knit to last 3, make 1, k2 – (64 stitches)
Purl row
K2, make 1, knit to 3 before the stitch marker, make 1, knit 2, slip marker, k2, make 1, knit to last 3, make 1, k2 – (68 stitches)
Purl row
K2, make 1, knit to 3 before the stitch marker, make 1, knit 2, slip marker, k2, make 1, knit to last 3, make 1, k2 – (72 stitches)
Stocking stitch the next 50 rows. (Knit one row, purl one row)
K2, Knit 2 together, knit to 2 before the stitch marker, SSK, knit 2, slip marker, k2, SSK, knit to last 2, Knit 2 together, k2 – (68 stitches)
Purl row
K2, Knit 2 together, knit to 2 before the stitch marker, SSK, knit 2, slip marker, k2, SSK, knit to last 2, Knit 2 together, k2 – (64 stitches)
Purl row
K2, Knit 2 together, knit to 2 before the stitch marker, SSK, knit 2, slip marker, k2, SSK, knit to last 2, Knit 2 together, k2 – (60 stitches)
Purl row
Knit 2, Purl 2 rib – Complete this over the next 24 rows
Cast off with around 40cm of yarn tail remaining. Use this tail to stitch up the side and bottom of your cover.
SSK is very simple and you can google it on Youtube.