The explore link was visible from our sign in page but I agree we can do better. I made it visible in the top menu of our static website with https://gitlab.com/gitlab-com/www-gitlab-com/commit/eaba29f4...
I'm not sure if we will keep it, that will also depend on how many people click on it.
On https://gitlab.com/explore there is a search field, for an example search please see https://gitlab.com/explore?utf8=%E2%9C%93&filter_projects=f-...