That really depends on the category. I find and bookmark new drugs every day, so naming any number of them is like being asked to name alphabetically what it's in my pantry; I could name a couple, but without a tag to mentally catalog them with, it'd be hard.
That being said, to name a couple of my favorite from different categories:
Antidepressant-- tianeptine (Stablon), the so-called sugar-coated antidepressant (named because one formulation is delivered in sprinkle-colored, sugar-covered tablets). It's a selective serotonin reuptake enhancer- it does the exact opposite of selective serotonin reuptake inhibitors (as the name would imply) by enhance's reuptake of serotonin from the synapse. It's effects are immediate, neuroprotective, side effects are minimum, good for depression as well as anxiety and attention deficit disorder, very good at treating stress-related disorders, and oddly enough an effective adjunct treatment in stabilizing Bipolar Disorder without the zombifying effects of similar treatment options. From the French studies on it's effects, it seems to improve emotional response/time to stress rather than numb it. Very cool, legal in the US (even though some places say it's prescription only).
Lanicimine- research chemical, successful attempt at creating a hallucinogenic-free NMDA-antagonist for treating depression, bipolar, and neuropathic pain (comparable to Ketamine). You'd be hard pressed to find it, but it's legal, and very effective at what it does.
Anxiety- Bromantane is still a personal favorite. It is the only drug in it's class of anti-asthenic simulants, that is, anti exhaustion. While most stimulants just increase access to energy and release energetic neurotransmitters, Bromantane actually treats exhaustion itself by promoting the endogenous production of dopamine to restore exhausted supplies- and by doing it endogenously, it uses the body's own pathways of increasing GABA reuptake, treating anxiety as well. Pretty cool.
Nootropics-- I don't know, there's a lot. PRL-8-53 is actually a life's-work drug created by a guy who is now deceased
almost 50 years ago(correction- he passed away last year. poor guy). The structure itself was rediscovered just this year by some people at longecity- they're working on a project to get an independent company to manufacture a large batch based on the old synthesis right now, actually. Some people on that forum call it one part of a "real life" NZT- one part cerebrolysin, one part PRL-8-53, and one part compound I can't remember right now... I can't link to the topic because it's technically sourcing, but it is legal, and it's pretty cool.
That paragraph my be slightly overblown- PRL-8-53 definitely has potential but with recent information that's been provided, it may be best to keep your hat on until more human experiences can be posted.
There's a lot of nootropics being investigated right now that are pretty fucking amazing. I'd go over to /r/nootropics to learn more about them.
Otherwise? Indeloxazine is pretty cool, it's an old "cerebral activator" from Japan for treating cerebrovascular disease and dementia. It's a serotonin releasing agent, norepinepherine reuptake inhibitor, NMDA antagonist, acetylcholine release facilitator, and 5-HT4A indirect agonist, so it's a nootropic, anxiolytic, antidepressant, anticonvulsant, and neuroprotective drug. Legal in the US, pretty cool. Structurally and theoretically, it may be similar to Tramadol (minus analgesia). Don't quote me on that though!
As for DMT friendliness? DMT has a pretty short half-life, so anything you take with it shouldn't interfere if you can have your blood levels of any other psychoactive not present. That is, if you're on a regular regimen of any psychoactive, it may interfere- that includes mostly serotoninergic drugs, kappa opioids, sigma agonists, etc. But DMT is so bizarre pharmacologically, and pretty underesearched, so I can't really condone the mixture of it with anything else in good conscious. However, it's your body, your mind, so you've got the final call. Just be careful.
Edit: Another great one-- sulbutiamine! Synthetic derivative of thiamine, it was created by Japanese scientists to treat thiamine deficiency (a real problem over there, because of rice being the staple food) because oral thiamine wasn't very bio-available. It acts as a stimulant and nootropic, and appears to reverse the flow of the dopamine transporter to dump dopamine back into the synapse, much like MDMA (except to a lesser extent). Strongly potentiates racetams, amphetamines, and caffiene, it also is unique in that treats social isolation itself (like what stems from depression and anxiety) as well as social anxiety- so it doesn't just make it easier to socialize, it makes you want to socialize! Furthermore, it increases the density of D2 receptors, so chronic use can lead to a normalized higher sensitivity to dopamine at that site (so after you stop taking it, you can be left with a better baseline for focus, motivation, creativity, etc). As an added bonus, it has been shown to effectively treat erectile dysfunction and improve memory. I love it, it's a really good "life enhancer" so to speak.