Hugo Duncan (Pallet etc) have made it possible to dynamically add new Maven/Leiningen dependencies from the REPL through Alembic.
This opens up from starting a repl with just Clojure and keep adding dependencies all night long.
As a courtesy to you, dear reader, a current project.clj of mine have the following deps so you can try them out for yourself, in the live-running repl.
Some of my common Project.clj dependencies
The Clojure language (which should already be available in the repl), functions for logging, parsing comma-separated values from exports and parse JSON from REST-apis.
Needed for ClojureScript code compilation. Probably outdated and I should switch to Pedestal instead.
A wrapper around Joda-time, the sane way to handle time, date and intervals on the JVM.
An http-client based on Apache Commons
The best working logging library IMHO.
Incanter is a R-like package for Clojure. There are functions for various statistics, matrix calculations, not-super-cool-but-convenient visualization through JFreeChart, readers for various data sets and more.
HTML Templating library based on transforms.
ClojureScript-library for manipulating the DOM.
A convenient, scalable, relational database that is built in Clojure keeping many of Clojure's idioms while getting the Durability in Clojures ACI-persistent datastructures. The exclusions is to make sure the logging from Datomic not collides with logback.
A convenient library to make ring-handlers for specified routes. If you come from PHP-world this is like where you put the "filenames" and/or the rewrite rules, only that it's made right from the beginning.
The servlet-abstraction library for clojure.
Small useful things, like the ColorBrewer colors.
I try to make visualizations with this one instead of D3, but it's less mature and I'm not skilled enough in the toolchain to get as much from it as from D3 right now. I have not given up yet!
Mocking is a way to create a fake instance of something, in this case it allows a ring handler function to be called to verify that the function returns excepted results, all this without starting a web-server, eliminating the possibility to have collisions in port-allocation etc.
A .pid contains the Process ID (an integer) as a string. This can be used to verify the process is running, and for kill it by a shellscript.
A cron-like scheduling library based on the Java concurrent scheduling libraries and some core.logic.