Just bought my oldest nephew a Lego Racer -- looks pretty cool. He's 8 and is big into Lego's, so he will enjoy putting it together...and then it should race.
Bought my 8 year old niece a "Sew Cool" sewing machine that allows you to make smaller things. This will be hit or miss, so stay tuned.
The rest of the nieces & nephews are younger - under 6. Bought the oldest boy a nerf gun and the youngest boy a Frozen coloring book / art case with markers, etc.
The rest of the girls are 4 & 6. I got the 4 year old a Frozen Activity book, and the 6 year old "Twister". I was able to get all 6 of them presents and spent less than $100, so I consider it a win.