Realtek Rtl8188 CUS USB dongle
Picture

Lsusb
Bus 002 Device 007: ID 0bda:8176 Realtek Semiconductor Corp. RTL8188CUS 802.11n WLAN Adapter
Lsusb -v gives:
Bus 002 Device 007: ID 0bda:8176 Realtek Semiconductor Corp. RTL8188CUS 802.11n WLAN Adapter
Device Descriptor:
bLength 18
bDescriptorType 1
bcdUSB 2.00
bDeviceClass 0 (Defined at Interface level)
bDeviceSubClass 0
bDeviceProtocol 0
bMaxPacketSize0 64
idVendor 0x0bda Realtek Semiconductor Corp.
idProduct 0x8176 RTL8188CUS 802.11n WLAN Adapter
bcdDevice 2.00
iManufacturer 1 Realtek
iProduct 2 802.11n WLAN Adapter
iSerial 3 00e04c000001
bNumConfigurations 1
Price
You can find this dongle in several brands, and around 4USD.