While researching the life of Hereward the Wake for a paper, my imagination was captured by the thought that during the years that Hereward was exiled, he may have been fighting with the Varangian Guard. There is no doubt that he was exiled and was fighting on the continent, most likely as a mercenary. The accounts say Flanders but there is speculation that he joined other Saxon nobles, dispossessed by the events of 1066, and went to Constantinople to join Alexius, Anna Comnena's father, fighting our old friend Bohemond and his father Robert Guiscard.
There is not much of a description of Hereward out there. He was not a tall man but rather solidly built so Bohemond would have towered over him. I think Bohemond would have beaten him just because Bohemond was so much larger but they would have been matched in ferocity and bravery. Both were capable military leaders with the charisma to attract followers although lacking a title and funds.
Before Hereward left for the continent, he most likely went north, possibly to help Malcolm fight MacBeth. It seems like Hereward managed to find himself in some of the most interesting places of his times.
He came home, hearing that the Normans had killed his brother and were harassing his mother. Whoever he was, when people heard he was back, they came to join him and his resistance army hidden in the fens of Lincolnshire. When William was about to break through the defences at Ely, Earl Morcar and Bishop Aethelwine opted to surrender and throw themselves on the king's mercy. They died in prison.
Hereward refused to surrender. He broke through the siege with a group of like-minded followers and disappeared into the Brunwald Forest. Later William made peace with him and restored all of his land since he could not subdue him militarily. After that there is disagreement over, if he ended his days peacefully and was buried at Croyland, or, if he was treacherously ambushed by disgruntled Normans and died, fighting off a whole crowd of them who would not have beaten him if four had not snuck up behind him and stabbed him in the back. It sounds as if he and Bohemond had much in common. The thought that they could have met on the battlefield amuses me but it really is not likely since I cannot see either man letting such a foe walk away without a fight.