I did a quick search and it seems Victorinox do (or did) make a bike tool. It's basically a compact allen key set with driver and a couple of detachable tyre levers. As it doesn't have a chain tool it's immediately off my list of potential bike tools. Also, I don't trust the built-in tyre levers that come with tools, they strike me as flimsy. I always carry a set of indestructible plastic levers that I once got free off a magazine.
I think my ideal bike combi tool would probably have a set of allen keys - (maybe just heads + a driver as is the case with the Victorinox one) plus straight and crosshead screwdrivers.. Chain tool. Valve removal tool (presta and schrader). folding Leatherman type pliers - I have a mini faux-leatherman and the pliers are incredibly handy. All in a case with a little pocket to store a few quick links of different sizes. If you can cram it in maybe even a little jewellers screwdriver for specs-related emergencies.
Possibly a spoke key - but in my experience the only use for a spoke key is making matters worse, but go on, throw it in.
Maybe disc brakes have some kind of important doodad that should be included. I don't know, I've never used them.
I don't think I've ever used the blades on my little leatherman, so I wouldn't need a blade. I definitely don't want flimsy built-in tyre levers.
What have I missed out?