Filegroup recommendation

Are there any general recommendations concerning filegroups? My personal point of view is to place large tables in their own filegroups and group smaller, more static, tables in a single filegroup. Is it also good practice to group small and large index in two separate filegroups or should each large index have their own filegroup? Are there any useful links out there concerning filegroups and configuration?http://www.sql-server-performance.com/filegroups.asp