With TeamViewer, you can remotely control multiple computers simultaneously from a single computer, which allow you to display your products and presentations without actually storing them locally. In addition, the program offers an integrated file transfer feature for you to copy files from one PC to another. The file transfer works even through firewalls, so it does not require any configuration. This program itself is very easy to use and to install and provides you with multiple communication options.
The program comes with modules to provide and get remote support/connection to and from anybody and establish VPN connections, all these free options not being for commercial use. The authors also provide extra services that you can buy on their website.
The only disadvantage that I noticed in this software is that the success of establishing remote connections depends on what version is installed on your computer. If you have an old version and you try to connect to a newer version, the program will request the version update to proceed with the connection.