Sucessful Integrations with different tools and services

List of few tools and services which I have successfully integrated or have come to know.

CAS -- The Central Authentication Service the most widely used tool works with almost all version of LR ,very less issues while integrating.
Read on -- CAS

Ease of configuration & integration with Liferay --- 4/5
Performance -------------------------------------- 4/5


SOLR -- features include powerful full-text search, hit highlighting, faceted search, dynamic clustering, database integration, and rich document (e.g., Word, PDF) handling. Solr is highly scalable, providing distributed search and index replication, and it powers the search and navigation features of many of the world's largest internet sites.
Read on --SOLR

Ease of configuration & integration with Liferay ---- 2.5/5
Performance -------------------------------------- 4/5

Terracotta -- Ehcache boost application performance, enhance operational control, and easily scale to large virtualized environments and clouds.
Read On

Ease of configuration & integration with Liferay --- 2.5/5
Performance -------------------------------------- 4/5

LDAP -- All open source LDAP work fairly good ,coolest features in LR 6.0
Read On Open LDAP

NTLM Works perfectly fine

Facebook Works perfectly however make sure to do cross browser testing use at least LR ver6.0.5

PayPal Works with almost all versions of Liferay

Alfresco It has been used in many project ,I am awaiting more feedback to comment on capabilities on different version
Read on Alfresco