robtillaart:
i have a lot of stuff to connect
Like what? just curious ...
Have you checked the I2C bus, it can connect up to ~120 devices ...
http://arduino.cc/forum/index.php/topic,127924.0.html
i will need :
LCD (1 pin)
Keypad (7 pins)
2x Sensors (2 pins)
2x fan (1 pin only on/off)
Gsm shield - https://www.sparkfun.com/products/9607 i dont know how much pins.... 
1 servo ?? (i dont know if it is that i want...) i will open 1-2 very light cardboard-like windows.... (i guess 1 pin)
4 Shift Register 8-Bit - SN74HC595 - COM-13699 - SparkFun Electronics? in order to control 30 leds.... (6 pins , 3pins/2shift registers)
1+7+2+1+?+1+6 = 18 pins...