Prior Art: Signed Hash Database

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Anyone is free to post a hash, along with a signature. Use of this site is at your own risk, and I provide no guarantees as to its stability or fitness for purpose. To use this site, create a document containing your idea, and append at least 74 random characters. Create a hash using SHA-2. Sign using GPG. Then upload both the hash and the signature. If at some later point you need to prove when you wrote the intial file, you can use the signed hash here, together with the upload time stamp, to prove a bound on when you wrote it. Simples! Why 74 random bits? Well, just for your own piece of mind. 74 ASCII characters take more than 512 bits to represent (518 to be exact). If they are chosen uniformly at random there is no way to compress that part of the document below 518 bits, which is longer than a SHA-2 hash. Thus there is no way you could have been tricked into uploading a compressed version of your document.

Current Entries

Viewing entries 21 through 30 (Total entries: 1630)

Hash:
Charles
Signature:
I like this site — user-friendly and packed with great stuff.

chicken road
Thursday, October 30 2025 - 04:07 PM
Hash:
Willis
Signature:
Dizaynı çox bəyənirəm!

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Thursday, October 30 2025 - 02:39 PM
Hash:
Peter
Signature:
Super platformadır! Uğurlar!

pinco bet
Thursday, October 30 2025 - 04:26 AM
Hash:
Latoya
Signature:
Нравится сайт — удобно
и много интересного.
онлайн казино
Wednesday, October 29 2025 - 09:29 PM
Hash:
Rachele
Signature:
ΠΑΝΑΓΙΩΤΗΣ ΤΑΝΤΟΣ & ΣΙΑ Ο.Ε.
ΑΝΤΑΛΛΑΚΤΙΚΑ ΑΓΡΟΤΙΚΩΝ ΦΟΡΤΗΓΩΝ
ΑΝΤΑΛΛΑΚΤΙΚΑ 4Χ4
ΑΝΤΑΛΛΑΚΤΙΚΑ 4Χ4
137ΧΛΜ Ε.Ο. ΑΘΗΝΩΝ-ΛΑΜΙΑΣ
ΚΟΜΒΟΣ ΤΡΑΓΑΝΑΣ ΤΚ 35200
ΕΛΛΑΔΑ - GREECE
ΤΗΛ. 2233092360
ανταλλακτικά toyota
Με έδρα την Αταλάντη, Τραγάνα, η εταιρεία έχει κερδίσει την εμπιστοσύνητων πελατών της μέσω της σταθερής ποιότητας και της αξιόπιστης εξυπηρέτησης.Η ΤΑΝΤΟΣ & ΣΙΑ προσφέρει
μια μεγάλη γκάμα υπηρεσιών που καλύπτουν κάθε ανάγκη των πελατών μας, από την προμήθεια
νέων και μεταχειρισμένων ανταλλακτικών αγροτικών 4Χ4 και αγροτικών φορτηγών 4Χ2 μέχρι τις πωλήσεις αγροτικών αυτοκινήτων 4Χ4.

ανταλλακτικα 4Χ4 (tantoscar.gr)
Tuesday, October 28 2025 - 11:10 PM
Hash:
Guy
Signature:
Bu saytda olmaq çox maraqlıdır.

1win onlayn oyunlar
Tuesday, October 28 2025 - 03:26 PM
Hash:
Leoma
Signature:
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Wednesday, October 22 2025 - 03:56 PM
Hash:
Eloy
Signature:
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Thursday, October 16 2025 - 03:37 AM
Hash:
Erik
Signature:
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Wednesday, October 15 2025 - 01:52 PM
Hash:
Armand
Signature:
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Tuesday, October 14 2025 - 12:42 AM
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