A few days ago, I discovered eshell/addpath which I find really convenient. A lot of my personal projects have a bin/ directory where I put various scripts, and this eshell function lets me do:
# from the root of my project
cd bin
addpath {pwd}
Then, the scripts in $project/bin are in my PATH, and I can freely execute them from wherever. The curly brackets in this context are eshell's equivalent of shell backticks.
(info "(eshell) List of Built-ins")
(I'm a little surprised by how much eshell has grown on me. I went from not liking it much to being quite fond of it. Once I gained enough proficiency in it, it became fun to use.)