The success of Business Intelligence (BI) applications depends on two factors, the ability to analyze data ever more quickly and the ability to handle ever increasing volumes of data. Data Warehouse (DW) and Data Mart (DM) installations that support BI applications have historically been built using traditional architectures either designed from the ground up or based on customized reference system designs. The advent of Data Warehouse Appliances (DA) brings packaged software and hardware solutions that address performance and scalability requirements for certain market segments. The differences between DAs and custom installations make direct comparisons between them impractical and suggest the need for a targeted DA benchmark. In this paper we review data warehouse appliances by surveying thirteen products offered today. We assess the common characteristics among them and propose a classification for DA offerings. We hope our results will help define a useful benchmark for DAs.