Normally I name these cookies with obscure names like '678768_cookie'
but I just wondering if there really is any point to this.
If someone is after the cookies from your site, he's likely to steal all the cookies found in the browser cookies file etc... Whatever the name is. So there is no point in using complex names, and the use of meaningful names is recommended (see this also).
I'm creating a bunch of cookies for a new website including username
and password - both encrypted.
It is a good idea to encrypt the username and password, as it hides some possibly important information, but - even encrypted - if someone would be able to steal the raw cookies from your computer browser, they would work the same on her computer.