I thought this had to be spelled out somewhere! 
I wasn’t sure myself so I did a bit of googling. I’ve only linked to my favourites above, and I haven’t tested them all. Feel free to add the links to more games here to save them from becoming lost and forgotten! 
Even the old homepage is still there, though the Worlds Directory is now empty: http://www.storynexus.com/
Here’s a link to a post where I collected a lot of info on StoryNexus games (including reviews).
I started playing Silver Tree a few days ago. Haven’t had the time to get that far in, but it’s functional. I appreciate the links to other ones worth checking out! While Silver Tree has some image errors on the homepage for it, it loads game assets when you’re playing.
Technical warning: These games appear to be HTTP-only.
You mean passwords are getting sent in the clear, or just that other people on your network can snoop on which storylets you’re playing?
I got quite far into Lethophobia a while ago and it worked fine until the game failed to recognise the presence of a quality and got stuck. Good as long as it lasted, though.
The login is also HTTP-only, and as far as I can tell passwords are sent in the clear.