Sooner or later you're going to destroy the microcontroller in your Arduino board, and to save money you can buy the ATmega328s directly without the Arduino bootloader. Therefore the next step is to upload the bootloader software which makes the "Arduino" world possible with your hardware. Although the procedure isn't new, instructables user 'frollard' has made a great video which explans the process very clearly, as shown below:
If your projects have outgrown your Arduino Uno-style board, consider moving up to a Freetronics EtherMega:
Quite simple the EtherMega is the fully-loaded Arduino-compatible board on the market today. Apart from being completely Arduino Mega2560-compatible, it includes full Ethernet interface, a microSD card socket, full USB interface, optional Power-over-Ethernet support and still has a circuit prototyping area with extra I2C interface pins. So if your project is breaking the limits, upgrade to the EtherMega today.