The Revised Report on Scheme or an Uncommon Lisp (1985) [pdf]

There is also s7 which can be embedded in C applications seamlessly.

https://ccrma.stanford.edu/software/snd/snd/s7.html

Gauche was made to get some real work done and as a result it comes with a kitchen sink and the entire forest.

There's also Loko if you want/need low-level operations.

[Reposting an old comment writen by myself.]

I use Racket. It has a lot of standard libraries and also packages that you can download.

Using only the standard librares I made a few projects:

* Open a GUI to select a file, untargzip it, parse one of the expanded files with xlm, edit the xml and targzip everything again. (This is a common pattern. Now many applications save the data as a xml compressed with tar and gzip.) I made an executable and send it to my coworkers so they can just run it.

* A bot to reply emails, with IMAP and SMPT. It reads the email, scrap some data from one of my webpages and send it in the reply. the bot can only only handle the easy questions, but in my case it's like the 90% so it it saves me a lot of time.

* I used the webserver so the T.A. in my part of the university can fill their preferences about the courses they want to teach. It handles like 500 users in an old computer without problems.