Back when I was in high school I ran my little brother through two several short solo campaigns: one (1st Edition AD&D) where he ran a fighter (and had two NPCs, a ranger and a cleric) on a quest to recover a powerful sword, and the other (Gamma World, 1st Edition) where he ran a mutant with no memories (not even of his own mutations - I revealed them as they came up in play) left for dead in a radioactive desert, who (over the course of the mini-campaign) found/rescued a mutant who would later become his wife, tracked down the person responsible for his near-death and memory loss, and got his revenge.
Many years later, I also ran my youngest son through a much longer solo campaign of Champions (1st edition again), where he ran an Iron Man type of superhero named Jetstar. That one lasted over a dozen sessions until it kind of petered out because we started our first 3.5 campaign with our current gaming group. But it was a good way for the two of us to get some gaming in between D&D campaigns.
Johnathan
Many years later, I also ran my youngest son through a much longer solo campaign of Champions (1st edition again), where he ran an Iron Man type of superhero named Jetstar. That one lasted over a dozen sessions until it kind of petered out because we started our first 3.5 campaign with our current gaming group. But it was a good way for the two of us to get some gaming in between D&D campaigns.
Johnathan