Why would you need a temperature logger? It seems that yesterdays facts aren’t interesting anymore. Anyway you still can find many places where you may find it useful.
Actually this is very simple and easy to build temperature recorder based on PIC12F683 microcontroller running at 4Mhz that measures temperature from thermistor resistor value via ADC. Temperature values then are stored to I2C 32kBytes EEPROM chip at desired intervals (1…256s). Device is capable to collect up to 32000 data points and consumes very little power as it goes to sleep mode between measurements. When recording is done just read EEPROM contents with PC software and plot, analyze or do whatever you need. BTW, why limit yourself with temperature – there can be other different (resistive based) sensors attached to ADC channels like light, gas, force, etc.