Or just use a MOSFET if the relay isn't very fussy. Or, use a combination of the Arduino driving something like the above timer relay, which itself will pull the 12V relay high if that's all it needs.

Arduino program to handle relays and control them using switches with support for double-click and long-press. Integration with home automation systems is possible through MySensors integration over ...

Default proxy setting when you install Arduino IDE is auto-detect. However the Arduino IDE won't connect to the proxy server on this setting. If I set the proxy server manually in Arduino it works ...