Geckoboard part was relatively easy - they have a nice interface to design beautiful looking dashboards.

Main magic was in the data pipeline. We tagged products that are Black Friday specific as seen on the merchant specific "Black Friday" category pages and other aggregators. These sites' pages were checked and the products' prices updated more frequently than our regular pipeline.

Everything ran as part of the Semantics3 infrastructure but at the last step we piped the updated information of the Black Friday specific products to a separate Postgres DB as well and that allowed us to run fancy queries that could answer almost any kind of questions we have about the data.