One of these in a pocket is all you need...

...don't leave homeworld without it!
Or if you aren't that connected then this...
...is the next best thing.
More seriously, it'd depend on your background and skills...
Pilot doesn't really need much of anything.
Navigator might have a handcomp.
Steward probably a favorite set of knives (for preparing meals, not stabbing people, usually... :smirk: ).
Medic would have his kit and some medical drugs.
Engineer would have a trusted multi-spanner*.
Gunner doesn't really need much either, except when doubling (typical imtu) as security, then add a choiced weapon and some body armor.
Everyone in general, if skilled, a weapon would be a good idea in most games.
* Don't know what they do in other games but imtu it's a complete mechanical/engineering/electronics tool set in one (deep, reinforced) pocket sized unit, complete with a scanner and diagnostic comp. Not as fully versatile as the complete set of tools in the ship's locker, but it'll do most jobs and it's always handy. Doubles as an excellent club in a fight.