Did Mozart ever write anything for cello? I have heard things about a lost concerto in F major but other than that nothing. I was wondering if anyone has heard of any cello works by him. I just find it strange that he wrote so many pieces and so many concertos but none for cello.

These Mozart works have prominent (and difficult) cello parts:
Divertimento for violin, viola, and cello, K 563; String Quartets Nos. 8, 9, and 10: in D, K575; B flat, K 589; and F, K 590, respectively.
In a slightly more romantic style, there are Schubert`s Arpeggione Sonata, and his great "cello" quintet in C major.