CacheFlow appliances have an advanced modular policy capability called Policy Function which is delivered to CFOS via CachPulse.
The functions can be enabled via GUI or Local Policy definition. Here are the list of available policy function as of September 2013:
CF5000#sh policy functions
Description: Remove the X-Forwarded-For header from client requests
Description: Enforce "safe search" mode for search engines
Description: Cache normally uncacheable requests for broadband speed measurements
Description: Enable the standard HTTP "Via" header in requests from the appliance to servers
Description: Enable the standard HTTP "Via" header in responses from the appliance to clients
Description: Use to increase download speed at the risk of bandwidth savings
Description: Use advanced techniques to cache content redirected or repackaged by upstream Service Provider caching; use only when upstream providers are actively redirecting/relocating content to alternate hosts.