I am working on https://hacktrack.info a SaaS that alerts you when a new CVE or exploit is published for the software you use. The idea came to me while working on an incident response team, where I noticed that many companies were hacked due to using software versions affected by recently published CVEs or exploits. Most of the similar solution I know of are really expensive or part of a larger product suite.
Shameless plug: I've been working on a project called https://hacktrack.info, that lets the user track the software they use and get an email alert when new CVEs are released for their stack.