Yes, I bought hundreds of them when they were very low in price throughout early 2017 to mid 2017. Over time as the price went up I sold them for a good profit then rolled most of that profit into Bitcoin starting when Bitcoin was only around $900 per coin, then I watched as Bitcoin increased in value to $20k, but sold many of my coins on the way up to the 20k. Hmmmm, if I only would have held out for $20k per coin, but you just never know when it has hit it's top before a bearish downturn!
The key for me was buying during a dip in the price (goes down), then holding onto them until their price increases to a minimum of 25% more then what I paid for them, if the price was moving up fast (a bull run) then I'd wait a while longer (50% to 60% increase to earn a bigger profit). So back then I'd buy 100 for $40 each for example, then begin selling them gradually once the price of each coin went over $50 to $64 or so.
Regardless of the price of Ethereum, co-founder Vitalik Buterin is working to cap the total Ethereum available to the masses at 144 million (Bitcoin is currently capped at 21 million) which would reduce the inflation on Ethereum and possibly force it to increase in price over time since there's a limited supply. So... the demand would increase but the supply would be capped so the result could be an increase in value. Again, it could also go down at anytime so only invest what you can afford to lose as there are no guarantees with crytocurrency and/or Federal laws etc.