Yeah man, you don't fuck with Bun-bun. The mini-lop knows his way around a shiv.
I don't know what my personal up-time record is. Back when I was working security on the night shift, 30-36 hours was not uncommon. Probably about 38-40 is my record, and my limit. I don't like driving when I'm up past 24 hours, sometimes I nod off at stop lights, or even just microsleep for a half second and snap to just before I'm about to jump the curb. Used to do that a lot working nights, driving home in the morning, 50 mile commute. Had an AWD Subaru that probably saved my life about once a week. Anything past thirty hours and I get weird, mercurial, and really, really wordy. Also, things get fuzzy, visually, like the outlines of things blur a little bit.
Right now I'm on my 24th hour, going for 30 or 32 to settle back into a day shift type rhythm.
Sometimes, though, you hit that sweet spot, or second wind, or whatever you want to call it. It's not so much the "how long" for me, as the "what time"; my best, most alert, most active and capable time of day is between 2000 and 0200. So even if I'm up on a long stretch, sometimes I hit that window and get a second wind lasting anywhere from a couple to maybe six hours or so, depending on how much caffeine/vitamins/nicotine I've had.
Mainly, though, I've just had my fill of 30+ hour consciousness stretches. After I left my night job, my sleep pattern was wildly irregular for years. Only recently, mainly thanks to melatonin supplements, have I been able to correct that (imperfectly, as today proves). I'm sure it hasn't been good for my health. It probably hasn't been real good for my sanity either. Couple times, felt like I was close to cracking up. You spend enough nights, awake, alone, staring at the ceiling, knowing the utter solitude of inhabiting that empty time, feeling like you're the only person in the world dumb enough or fucked enough to be seeing sunrise from the wrong side day after day after day... it gets to you. It got to me.