Definitely in agreement that the cost of caffeine is a non-factor in the cost of energy drinks vs. other soft drinks.

I don’t believe Sigma Aldrich sells to the general public though, do they?

Personally, I prefer the loose powder vs. preportioned capsules or pills, since it allows me easier control over the dose. When I use caffeine powder, I usually mix it into a drink and just sip on it, rather than take it all at once. Sometimes I just want some herbal tea or a sparkling water with a little extra caffeine… I want the caffeine of coffee or energy drinks, but I don’t want the flavor. Way back in the day, I’d add about 200mg caffeine to a 1L bottle of water and sip on that until it was about halfway gone, then top it off with more water to dilute the remaining caffeine.