I'm a very busy person, so any time I'm asked to do something that isn't strictly classified as "fun", I look at the time-value of the activity to see if it's worth my time - literally. I've found renting stuff out on Loanables to be one of the most profitable things I can do, given the amount of time it takes.
For example, I often rent out my Cash Flow board game, which is great for teaching people financial responsibility. It typically rents for at least 1 week, which fetches me $12. It takes about 5 minutes of my time each time someone rents it. $12 in 5 minutes equates to $144/hour.
Another popular item is my jon boat, which I rent to neighbors who just want to go fishing for a day or weekend and don't want to deal with the hassles of boat ownership. My boat rents for $30/day and most people keep it for 2 days, so that's $60. It takes about 30 minutes of my time each time I rent it, so that's $120/hour.
I find that most items that I rent fetch me around $120 - $180 for each hour of my time. That's not a bad hourly rate, and certainly worth a few minutes of time. Plus I get the added benefits of meeting some great neighbors and feeling good about helping them AND the environment.