With this device you can connect multiple monitors to your computer: Plugable USB-VGA-165 USB to VGA Adapter for Multiple Displays up to 1920×1080 / 1600×1200 Each (DisplayLink DL-165 Chip). Supports Windows 8.1, 8, 7, and XP. Also works with the Apple products, such as MacBook Pro.
Why the need of multiple monitors? Obviously, this application can be used for multitasking. One can employ multiple screens for communication, office work, data, etc. No more switching between windows and losing your place.
Scenario: Connect three or more monitors to your laptop or desktop PC (one adapter required per monitor, up to 6 total monitors on Windows PCs.
The Plugable unit is not currently supported on Linux, but another adapter is available: Sabrent USB 2.0 to HDMI Adpter for Multiple Monitors with HDMI/DVI Adapter up to 1920×1080/1600×1200 Each (DisplayLink DL-165 Chipset) USB-HDMI. Linux and Mac beta-quality drivers available but with important limitations.