I created a small program called Singleton Remover CSV to help researchers process files quickly that might otherwise take a long time to be handled by hand. The program simply compares ID values given in the first two columns of a .csv file, saves any matching rows, and discards the rest.
Originally, the program was made to support a specific use case in bioinformatics operational taxonomic unit (OTU) analysis. Essentially, a researcher could provide a list of desired OTUs for preservation in the first column of a .csv file and a full collection of OTUs in the second with any associated data in the following columns. Singleton Remover CSV will return a .csv file that only contains data associated with the desired OTUs.
However, the program is potentially useful for anyone who needs to reduce a dataset through comparing IDs in a similar manner. Therefore, I made Singleton Remover CSV free to use with the full source available from GitHub. The program is available as an Adobe Air installer and as a .fla that can be compiled with Adobe Flash CS5 or higher.