Under saddle bags

[iFKA]

I always take my cell phone, some money and my identity card (cause it can be used as my health card in emergency cases),sometimes I like to take one or two energy bars and my lip balm. And that's it!
You should also take spare tire and, of course, pump. I don't take it cause my darling has it always with him, and we usually ride together on rides that are longer than 50km.

[Grog]

In seat bag for any ride:

1 spare tube
1 patch kit
1 CO2 adapter
2 CO2 cartridges (the big ones)
2 tire levers
1 multi tool (which includes hex keys, philip and flat screwdriver, more tire levers, chain breaker, and other stuff) and the diagram explaining the tools I never use on the multitool, in case I need something that I can't recognize.

I should add a $20 bill in there.

In my jersey pockets:

If it's a winter ride, another spare tube and another CO2 cart, and another pair of gloves
A spare pair of gloves
Whatever food I think I'll need, + 1 unit for the eventual bonked rider I'll meet

I also have a frame pump with a pressure gauge.

And two water bottle cages with assorted drinks (usually water + lemonade if a long ride).

[7rider]

In my road bike's saddle bag is a spare tube, a patch kit, and 2 tire irons. I like to keep ID, cash, and cellphone in my jersey pocket, in the unlikely and unpleasant event that I am physically separated from my bike. For longer rides in your mentioned range, I'll throw a gel or two in my pocket. Maybe a Cliff Bar or something more substantial to gnaw on.
Oh, and the saddle bag is a Pedros bag - made from recycled inner tubes. Very small, very minimalist, and I quite like it.