In need of Alarm clock program

[M0n3y0nf1r3]

Hey all, well tommorow I have to get up to study for a Spanish final, but I dont want to sleep through it. My cell phone and regular alarm clock have 0 reliablity so im wondering if someone can suggest a computer alarm clock to me. Ive googled for a bit, but Im wondering if anyone has a trusted one, because I dont want to download some spyware chunked program.
Thanks,
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