I'll say it: I think any ring with adequate electronics will be too bulky and uncomfortable to wear on a toe, especially if you put it into a shoe. Also, how much more info could you get from the foot's motion than from something on the wrist? Finally it's not clear what sensors could be useful beyond the IMU anyway.

I don't know why people are being squeamish about this.

Time to check your rings! You are behind by 300 thrusts for this time of day compared to your average this week.

I did think about it but didn't say out of respect for HN

In the interest of appearing professional, I'm trying very hard not to but damn it's a real struggle.

On reddit for sure, check it there