The document lists 20 big data projects using Hadoop. The projects focus on using Hadoop for tasks like clustering electricity consumption data, optimizing job scheduling in MapReduce, partitioning and aggregating data for MapReduce applications, predicting patient wait times in hospitals using big data, frequent itemset mining, modeling Hadoop performance, scheduling MapReduce applications across heterogeneous environments, optimizing speculative execution, privacy protection, K-nearest neighbor joins, dynamic resource allocation, predicting customer churn, improving Hadoop performance using related job metadata, adaptive HDFS replication using machine learning, auto-tuning Hadoop configurations, efficient data encoding for cloud storage, analyzing geographically distributed datacenters, distributed in-memory processing of queries, and processing Cassandra datasets with