Here are some high Domain Authority (DA) and Page Authority (PA) directories that can be beneficial for a web hosting business:
DMOZ (Open Directory Project) - Though it's not actively maintained now, it had high authority.
Best of the Web (BOTW) - A respected directory with good authority.
Yahoo Directory - Offers a prominent directory listing with a significant impact.
Directory Critic - Lists various directories with their metrics; you can find high-authority ones.
Web Hosting Directory - Specific to the web hosting niche, it offers listings and reviews of hosting providers.
Ensure these directories align with your niche and adhere to quality guidelines to benefit your web hosting business.