Thinking of PS1 titles on the 3DS with its 64mb of ram, I remember the GP2X Caanoo, a device with 128mb of RAM, is capable of running PS1 titles.
Although I don't really know any of the technical stuff behind what makes that possible on the Caanoo. It does have a 500mhz processor that safely overclocks to 750mhz, possibly 800mhz with luck.
There's a thought, can the 3DS even be overclocked?
Well, I'd guess "yeah", but like past systems it would just make EVERYTHING run at fast speeds, speeding things up.