The PSP and the PSVita have a decent amount of homebrew in common such as Tyrian, Super Mario War, Minicraft and others. However, thereís one homebrew that few expected anyone would try to port to the Vita and that is DaedalusX64, the PSPís Nintendo 64 emulator which only works somewhat well because the N64 and PSP share the same CPU architecture (MIPS).

DaedalusX64does a pretty admirable job at emulating the N64 considering the hardware itís working on and can actually deliver playable framerates on titles like Super Mario 64 and Mario Kart 64. Recently, thereís been some work to improve its performance, stability and compatibility with some titles by z2442 and others; updated versions resulting from this work can be downloaded from here.
As of right now, the folks behind this porting effort havenít been able to compile/build it for the Vita but this might change in the near future although itís unlikely that it would perform too well. From some comments on the Reddit thread about this port, TheMrIron2 (who contributed to the aforementioned updated DaedalusX64 builds) states that there may be an attempt to access the PSP hardware found inside the Vitaís SoC to improve emulation performance although this idea has never been employed in any homebrew in the past and itís unknown whether itíd work.
For more information about the matter, you can check out this Reddit thread and get on the PSP Homebrew Server Discord channel as thatís where TheMrIron2 and other people behind this port seem to be discussing stuff.