Pretty much what the post title says – Portable Freeware is excellent collection of portables maintained by Andrew Lee. Since 2004 site had amassed more than 1200 titles of software in numerous categories.
Site itself has light design and loads very fast. Software entries always have links to app website, screenshot, direct download link (if available) and blog style comments.
Only downside is considerable update lag – it often takes up to week for information on new versions to appear there.
Site is focused on being ultimate portable catalogue which it fulfills perfectly.