WiFi ISM 2.4Ghz 802.11 b/g/n ESP8266 Serial Transceiver Module ESP-07

All the I/O pins are broken out and you can design your PCB around this, or simply nudge some inline connectors to the PCB for a quick solder job, or solder some tiny tiny wires into the holes. Furthermore this ESP-07 variant has the "metal housing" for extra shielding. 
 
This is a WiFi serial transceiver module, based on ESP8266 SoC. The SOC has Integrated TCP/IP protocol stack. To get started and for a couple of tutorials, see the "Resources" links below. ESP8266 is a highly integrated chip designed for the needs of a new connected world. It offers a complete and self-contained Wi-Fi networking solution, allowing it to either host the application or to offload all Wi-Fi networking functions from another application processor.
 
ESP8266 has powerful on-board processing and storage capabilities that allow it to be integrated with the sensors and other application specific devices through its GPIOs with minimal development up-front and minimal loading during runtime. Its high degree of on-chip integration allows for minimal external circuitry, and the entire solution, including front-end module, is designed to occupy minimal PCB area.

• SDIO 2.0, SPI, UART
• 32-pin QFN package
• Integrated RF switch, balun, 24dBm PA, DCXO, and PMU
• Integrated RISC processor, on-chip memory and external memory interfaces
• Integrated MAC/baseband processors
• Quality of Service management
• I2S interface for high fidelity audio applications
• On-chip low-dropout linear regulators for all internal supplies
• Proprietary spurious-free clock generation architecture
• Integrated WEP, TKIP, AES, and WAPI engines

• 802.11 b/g/n
• Wi-Fi Direct (P2P), soft-AP
• Integrated TCP/IP protocol stack
• Integrated TR switch, balun, LNA, power amplifier and matching network
• Integrated PLLs, regulators, DCXO and power management units
• +19.5dBm output power in 802.11b mode
• Power down leakage current of <10uA
• Integrated low power 32-bit CPU could be used as application processor
• SDIO 1.1/2.0, SPI, UART
• STBC, 1×1 MIMO, 2×1 MIMO
• A-MPDU & A-MSDU aggregation & 0.4ms guard interval
• Wake up and transmit packets in < 2ms
• Standby power consumption of < 1.0mW (DTIM3)
• Dimensions: 20mm x 16mm