PocketGo Retro Gaming System.

[zapiy]

You can add your own games via a Micro SD card. Over ten systems from classic handhelds to home consoles are supported with the custom firmware and more are being added regularly. The PocketGo is very portable at just 12.3cm x5.6cm x 1.4cm (much smaller than Revo k101), it is ideal for a quick pick up and plays. And with save support, you can continue at any time even if the original game did not support it.

    Play your favorite retro gaming classics on one portable handheld
    High quality 2.4" IPS Display Screen (tempered glass)
    Supports save states, save then continue where you left off at any time
    Add your own games via Micro SD card.
    Upgrade to custom firmware to add even more classic gaming systems

Features:

L, R buttons, the volume dial
Loads games from MicroSD card (no games preloaded)
Supports game types: NES/GB/GBC/GBA/SNES/SMD/SMS/PCE/NEOGEO/ MAME/ PS1
Save/Load game progress

Specs:
CPU: Allwinner F1C100S
RAM: 32MB
Screen: 2.4" IPS 320x240 (tempered glass)
SDCard: supported up to 128GB
Buttons: L, R, the volume dial, switch on/ off, Reset
Port: TV- out, Headphone Jack, Micro SD card slot
Battery: 1000mAh
Dimensions: 12.3cm x5.6cm x 1.4cm
Weight: 100G

Includes:

PocketGo Retro Game Handheld
USB cable
User manual
Micro SD card

Thoughts on another system like this?

[TrekMD]

There seem to be so many of these lately.  It does look nice, though.