The parts you need are:
3 Capacitors (from 470uF to 4700uF, each),
a 2N3904 transistor,
a 2N3906 transistor,
a resistor(1k to 10k ohm),
a solar cell (minimum 3 volts )(i used two 2 volt cells in series),
a pager motor(or a vibrator).
you'll also need a blinking/flashing LED (FLED ).
to help you, i have made a, very easy to follow , schematic of the circuit, which can be found on http://fc09.deviantart.net/fs71/f/2010/052/a/f/FLED_circuit_by_kattejuice.jpg
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