The is intense. I've often thought about the Russian Venus lander. In the same vein I occasionally think about what could survive deep within the Earth. Of course I then immediately get tripped up wondering if any useful satellite could be made to work within the Sun, and that's where I realize I should just think about something else.
In The Killing Star by Charles Pellegrino and George Zebrowski, one group of survivors orbits a ship around the Sun, just below the chromosphere. There's also a story about "distilling antihydrogen" near the Sun, in Vernor Vinge's Marooned in Realtime.
David Brin's Uplift series had mechanised lifeforms "floating" on the sun to collect matter, and IIRC Sundiver has life forms floating in the chromosphere.
