Being a fan of catheters, I tried one (10fr/5cc) like a feeding tube thru my nose.
I have no clue where this idea came from... The balloon was inflated to about 3cc. While this doesn't sound like an enema, it unexpectedly turned into one.
I used a new enema bag with plain water, and connected the tube to the catheter, clamped the flow to a trickle, and took 2L over about 45 min. 20 mins later, my colon started gurgling, and urgently wanted to let it flow. I essentially took a colonosopy prep, although it was way less violent.
The catheter tube worked brilliantly to take the water, without having to swallow or drink. No taste, either. No gagging, no drama.
So moral of the story, if you need to take a lot of liquid by mouth, or the liquid tastes horrid, try the feeding tube method. I suppose a large syringe would work to intake the fluid if there wasn't a large amount to take. The small bore of the catheter I used served to restrict the flow to where it was unnoticable.