Python's interactive mode is very convenient, because you can try simple stuff without having to write it to a script first. Since I had to do a lot of VBScript at the time, I wanted to have something like that for VBScript too.
I found this blog post that had almost exactly what I wanted, except for line continuation. Which is what I added (for my own convenience). Plus some other convenience features, like importing other VBScripts, or looking up help topics in the VBScript help file.
Put vbsh.vbs and vbsh.cmd into a directory in your %PATH%. That way you
can invoke it by typing vbsh in a Command Prompt. Optionally put init.vbs
into your profile directory (%USERPROFILE%) and modify it as needed.
A simple interactive VBScript Shell.
help Print this help.
! EXPRESSION Shortcut for 'WScript.Echo'.
? Open the VBScript documentation.
? "keyword" Look up "keyword" in the documentation.
The helpfile (script56.chm) must be installed
in either the Windows help directory, %PATH%
or the current working directory.
import "\PATH\TO\my.vbs" Load and execute the contents of the script.
exit Exit the shell.
Customize with an (optional) init script '%USERPROFILE%\init.vbs'.
Note that help lookups will only work with the english version of the Windows
Script Technologies help file (script56.chm) present on your system, as
other language versions of that file have different internal paths. The CHM file
must be located in either the Windows help directory, the %PATH%, or the
current working directory.