Users with laptops with Optimus technology might be interested: 

Ubuntu community has launched dedicated repository for the latest Nvidia drivers (read more here: http://goo.gl/sF3YMm). I have tested it and can confirm that version 352 and 355 (beta) both run fine on Kubuntu 15.10 (Wily). 

Since highest version available through Driver Manager is 346, this repository provides an easy way to use latest one.