How to get a list of custom Powershell functions?

One solution for you is to put all your functions in a psm1 file and create a module. That way you can import the module and have all the commands in a nice module.

To get a list of available functions

> Get-ChildItem function:\

To remove a powershell function

# removes `someFunction`
> Remove-Item function:\someFunction

Add this to your profile:

$sysfunctions = gci function:
function myfunctions {gci function: | where {$sysfunctions -notcontains $_} }

and myfunctions will list just the functions that were created since the session started.