Inventions that could have come later: I'm guessing that sans World War II nuclear weapons and space-capable rockets would have been delayed a good ten to fifteen years.
Oops. I'm in pre-1900 land aren't I? Okay. Pre-1900. How about steam warships? Was the tech good enough for Napoleon to have gotten them? Steam ships, certainly, but I'm not sure if the tech was good enough for warships.
How about steam locomotives? It would be interesting if Napoleon ripped off Watt's steam engine and managed to get someone to improve it enough to start building a system of steam locomotives. He would have incentive to do that given Britain's naval dominance. Move at least some commerce away from the British dominated oceans. I'm not sure that steam engines were reliable/powerful enough early enough for that. Of course since this is alternate history we can presumable handwave any missing pieces of tech into existence 15 to 20 years early.
Oops. I'm in pre-1900 land aren't I? Okay. Pre-1900. How about steam warships? Was the tech good enough for Napoleon to have gotten them? Steam ships, certainly, but I'm not sure if the tech was good enough for warships.
How about steam locomotives? It would be interesting if Napoleon ripped off Watt's steam engine and managed to get someone to improve it enough to start building a system of steam locomotives. He would have incentive to do that given Britain's naval dominance. Move at least some commerce away from the British dominated oceans. I'm not sure that steam engines were reliable/powerful enough early enough for that. Of course since this is alternate history we can presumable handwave any missing pieces of tech into existence 15 to 20 years early.