Q:

How to open the Recycle Bin from the Windows command line?

How do I open the Recycle Bin from the command line? 
I'd be very glad if there is a built-in Windows command.

A:

Command line
On the command line, type
start shell:RecycleBinFolder

It is not case sensitive, so you can just type start shell:recyclebinfolder.
Run dialog
An alternative is to use the Run dialog (menu Start/Run or Win + R) - there is less to type. Type
shell:RecycleBinFolder

and press OK (or hit Enter). 
It is portable!
This method works on all versions of Windows, at least back to Windows 2000.

A:

(Depending on the OS and filesystem, the directory may be $Recycle.bin, Recycled, or Recycler.)

To open the Recycle Bin window (showing deleted objects on all drives):
C:\> start ::{645FF040-5081-101B-9F08-00AA002F954E}
or
C:\> start shell:RecycleBinFolder
or
C:\> start C:\$Recycle.bin

To list deleted objects on a specific drive:
C:\> dir /s/a <driveletter>:\$Recycle.Bin
(NB, the original filenames will not be shown in this mode.)

A:

You can open the Recycle Bin window by using its GUID:
explorer ::{645FF040-5081-101B-9F08-00AA002F954E}

