Ok, I tried this the other day. First of all, it is a b*tch to get the fuzzy "wick" thing out to get oil back in the bulb, but it is possible with some time, effort, and tools. I almost poked my eye out with the needlenose pliers. Second, they must cut the oils with something mysterious. I tried straight FO and then tried it with cyclo (I have no idea why...LOL...just an experiment) and I couldn't get much scent throw. In fact, I think the minimal scent throw I was getting was primarily from FO spilled on my counters! I would love to know what they mix the FO with though. I'd also love it if a supplier would develop refill bulbs for these so we can easily offer customers refills and not have to destroy the original bulbs trying to get the cap off (the BBW bulbs are definitely not a screw off cap--more of a "pull with all your might until the mangled lid pops off cap")