Are you looking for PhD positions in Mathematics and Computer Science (or something related) in the Netherlands (or Belgium nearby)? Then you may like to join this mailing list managed by yours truly. In this list, I forward the emails about new open calls for PhD positions that I get through my network. Also, the mailing list members can submit their posts as well.
The list is actually a google group, so if you have trouble signing up without a google account, contact me, preferably by email which you want to use to sign up, and then I will send you the invitation manually. Don't forget to mention some non-empty subset of words 'PhD positions NL mailing list' somewhere in your message so I know what you are talking about.