Ketamine, hands down. My favourite drug (when I didn't have my sky rocketed tolerance). Perfect for a gift and I'd give them a nice 100mg, split into 2 bumps, spaced out by 10 minutes. Perfect for a first timer.
EDIT
On Ketamine's addictive qualities, ya, they totally exist. After my first time, what did I do when I came down? I thought, my god! Another bump for the tripper! And spent the next 2-3 hours taking bumps...That was my FIRST time, lol. I've actually toned it down a lot though. Haven't had any in 3 weeks, maybe 4? But my tolerance is still there, it will likely never leave. So for the first timers that I introduce it to, I always tell them to take me as an example as to why to NEVER do it everyday and to do it only once a week. When they see me rail a 250mg line and seem pretty close to sober, after they just did 1/4 of that and are flying, they're usually convinced not to follow in my dumb foot steps. Anyone else on these boards do what I did? Binge Ketamine for a couple weeks, spaced by sometimes a couple months? God damn tolerance still though, eh? Err, sorry, I ramble about Ketamine. I love discussing it, even it's shitty tolerance forming ways that never go away and leave you with next to no buzz, thus the beauty being gone forever.