I'd like to follow this thread for the same reasons as Matt.
What I do wonder is if some unregulated mods have safety features, for those more used to regulated mods.
For example, a safety switch to prevent auto firing, maybe a fuse, and other things more experienced vapers can suggest.
I only have a FuHattan that I am timid about using, unless in the company of experienced vapers.
As for what to put on top, the Ijoy Unlimited looks easy to wick, sort of an RDTA. I hear Genny's can be a PITA, but an RDA with some tank capacity is interesting. Never got into the motion of dripping, just feels unnatural to me.
Ugh, now I have another thing I have to buy

, I have the Haze, Theorem and Avocado, those bottom tank/top coil/RDTA/whatchamacallits are nice. They all have their own little quirks, and you do have to tip them upside down sometimes to get juice into the wick but they are nice.
Anyways, for the other question, I can think of one that is an unregulated but protected mod. CF Mod, it's a tube but it has a cutoff fire time, and won't fire below ~.15Ω and will stop firing when the battery is low. But, it gives the no variable controls, just the strait voltage from the battery. I like the little guy and was my travel piece for a long time. No need to worry about any bad things when my brother sits on it (happened more than once).
To Mattp, you already had the dos equis recommended, but give the tres equis a look. If you like the reuleaux design it's very similar and you get an extra battery. It's very easy to take apart and clean, clone is like $25. More battery life and available current but still in a pretty small package for what you're getting. It has a few little quirks but once figured out it's a great toy (I loved the first one I got so much I ordered a second).