At home, I use Thunderbird, and it has an add-in called 'Nostalgy'
that saves me time and frustration. I've looked unsuccessfully for
something similar for Outlook, which I use at the office.

The Nostalgy add-in allows me to move (or copy) emails to folders
using only the keyboard, or to open a folder with the keyboard. Since
I have 1.73 bazillion hierarchically arranged folders, this is much
easier than using the mouse to open sub-folder after sub-folder, or
scrolling down the folder list if I have a bunch of folders open.
Three keystrokes initiate the action, depending on whether I want to
move, copy or go to a folder. That opens a list (it happens to be a
list coming up from the status bar, sort of like a pop-up) of the ten
most recent folders that I've worked with. I can select an item from
that list using the up or down key, or I can start to type part of the
name of a folder. For example, if the folder I'm looking for was
labeled Languages/Semitic/Arabic, I could start by typing 'l' for
'languages', which would give me a pop-up listing all the folders
containing the letter 'l' somewhere in their path; if I then typed
'a', that would narrow it down to all folders containing the string
'la', etc. But I could just as well type 'r' for (the second letter
of) Arabic, and so forth.

Once I've narrowed the pop-up down to a single folder--or
alternatively selected the right one with the cursor key--hitting
enter accomplishes the desired action of moving or copying the
currently selected message to that folder, or opening that folder.

There's a fuller description of Nostalgy, including screen shots, at
https://addons.mozilla.org/en-US/thunderbird/addon/2487.

Is there any similar add-in for Outlook?

Mike Maxwell