Tesla Adapters
You can purchase a very capable Mobile Connector for Teslas that supports a wide range of plug in adapters for eight different electric plugs. While the Mobile Connector comes with an adapter for a 15A household receptacle, you can buy other adapters from Tesla for many other receptacles. You can also buy adapters from EVSE Adapters for many other kinds of plugs (like a NEMA 6-30 or locking plugs).
Other Plugs
Occationally, you might find yourself in a location that has an unusual receptacle. Marine ship to shore plugs, TT-30 travel trailer plugs, or even trying to recharge from a generator that has a locking plug. In these cases, you'll probably have to buy or build your own adapter.
Marine and Temporary Power
If you take a long trip to your or a friend's boat dock, this will come in useful. Many marinas have these 50A 240V receptacles for ship to shore power. The plug is a NEMA SS2-50. The interesting thing about this plug is that it is almost identical to the plug used for large venue temporary power. I've been to outdoor events where these plugs are literally all over the place. The temporary power plug is the CS6365 also known as a California Style plug. The only difference between it and the NEMA SS2-50 is the addition of a center pin.
Here is a manufactured adapter that will plug into EITHER the NEMA SS2-50 or a CS6365 and adapts it to a NEMA 14-50. You can then use the NEMA 14-50 adapter with your MC.
Note if you are planning on charging at a marina, check to see what kind of receptacles they have ahead of time. Like RV camp sites, a given marina might only have 30A connections instead of the bigger 50A connections. The 30A connection could be a TT-30 (see RV section for adapter) or a 30A 120V twist lock that will require a different adapter.