a few days ago I came accross this great add-on board for the Arduino UNO with DIP socket ATMega328: http://www.hobbytronics.co.uk/arduino/arduino-uno-pro
The Arduino UNO*Pro – Upgrade which transforms your Arduino UNO powered by a ATMega328 into a pro version running an ATMega1284p. Once I read about it on twitter I just ordered two of them to see how it goes.
Just removed the old uC, added the extension board and copied the board files into the hardware folder as described in the product description page at hobbytronics.
Now your Arduino UNO is capable of ealing with sketches up to 130kB Great upgrade. Let’s see what I can do with it.