Unseen Servant possible uses

[cea]

give a small box containing a light object to unseen servant.

turn on or off the light whenever you want
just simply saying the command open/close the box...

good choice of light object is a small stone with light spell.

 

[sneerglaw]

You can use unseen servant to shuffle around wands and weapons amongst your party during combat. If you add a handy haversack you can free up a lot of economy.
Ie I often have my servant trade wands between myself and my familiar. Or to take a wand out of my haversack and hand it to my familiar, which would otherwise use my turn to take a wand out of the haversack and hand it to my familiar.