What is Alma: http://www.exlibrisgroup.com/category/AlmaOverview
Alma documentation (no login required): http://knowledge.exlibrisgroup.com/Alma
Alma recorded training (no login required): http://knowledge.exlibrisgroup.com/Alma/Training
Alma APIs: https://developers.exlibrisgroup.com/alma
Alma impact and value reports gathered from existing Alma customers: https://knowledge.exlibrisgroup.com/Alma/Product_Materials/Overview_Materials/Impact_and_Value_Reports

UK institutions live with Alma:
Abertay University: https://library.abertay.ac.uk
Aberystwyth University: http://whel-primo.hosted.exlibrisgroup.com/primo_library/libweb/action/search.do?vid=44WHELF_ABW_VU1&reset_config=true
Anglia Ruskin University: http://libweb.anglia.ac.uk/
Bangor University: http://www.bangor.ac.uk/library/
Cardiff Metropolitan University: http://whel-primo.hosted.exlibrisgroup.com/primo_library/libweb/action/search.do?vid=44WHELF_CMU_VU1&reset_config=true
Cardiff University: http://www.cardiff.ac.uk/libraries
Coventry University: http://locate.coventry.ac.uk
Edinburgh Napier University: http://librarysearch.napier.ac.uk/
Glasgow Caledonian University: https://discover.gcu.ac.uk
Glyndwr University: http://primo.glyndwr.ac.uk/
Heriot Watt University: https://www.hw.ac.uk/is/find-resources.htm
Imperial College London: http://www3.imperial.ac.uk/library
Keele University: http://www.keele.ac.uk/library/
Kingston University: http://icat.kingston.ac.uk
Lancaster University: http://libweb.lancs.ac.uk/
Liverpool John Moores University: https://www.ljmu.ac.uk/microsites/library
LSE: http://www.lse.ac.uk/library
National Health Service (NHS) Scotland: http://www.knowledge.scot.nhs.uk/home.aspx
National Health Service (NHS) Wales: http://nhswaleslibrarysearch.cardiff.ac.uk
National Library of Wales: https://www.llgc.org.uk/
Natural History Museum: http://www.nhm.ac.uk/research-curation/science-facilities/library/
Newcastle University: https://libsearch.ncl.ac.uk/primo-explore/search?sortby=rank&vid=NEWUI&lang=en_US
Northumbria University Newcastle: http://library.northumbria.ac.uk/home
Open University: https://pmt-eu.hosted.exlibrisgroup.com/primo-explore/search?vid=44OPN_VU1&lang=en_US&sortby=rank
Plymouth University: http://dc03vg0067eu.hosted.exlibrisgroup.com/primo_library/libweb/action/search.do?dscnt=1&fromLogin=true&dstmp=1367331315760&vid=PLY_VU1&fromLogin=true
Royal Holloway University of London: https://www.royalholloway.ac.uk/library/home.aspx
Royal Welsh College of Music & Drama: http://librarycatalogue.rwcmd.ac.uk/primo_library/libweb/action/search.do?vid=44WHELF_RCMD_VU1
Salford University: http://www.salford.ac.uk/library
Sheffield Hallam University: http://library.shu.ac.uk/
Swansea University: http://whel-primo.hosted.exlibrisgroup.com/primo_library/libweb/action/search.do?vid=44WHELF_SWA_VU1&reset_config=true
University of Bath: http://www.bath.ac.uk/library/
UCLan (University of Central Lancashire): http://www.uclan.ac.uk/students/study/library/index.php/valnow/
University of Cumbria: http://cumbria-primo.hosted.exlibrisgroup.com/primo-explore/search?vid=44UOC_VU1
University of Dundee: http://www.dundee.ac.uk/library/
University of East London: https://uel-primo.hosted.exlibrisgroup.com/primo-explore/search?vid=UEL_VU1&lang=en_US
University of Edinburgh: http://www.ed.ac.uk/schools-departments/information-services/library-museum-gallery
University of Leicester: http://www2.le.ac.uk/library/
University of Manchester: http://www.library.manchester.ac.uk/
University of Sheffield: http://find.shef.ac.uk/
University of South Wales: http://studentlibrary.southwales.ac.uk/findit
University of Strathclyde: http://suprimo.lib.strath.ac.uk/
University of Surrey: http://www.surrey.ac.uk/library/
University of Sussex: http://www.sussex.ac.uk/library/
University of Wales Trinity St. David: http://www.uwtsd.ac.uk/library/catalogue/
University of Westminster: https://www.westminster.ac.uk/library-and-it
University of the West of Scotland: https://uws-primo.hosted.exlibrisgroup.com/
University of York: http://www.york.ac.uk/library/

A small selection of institutions live on Alma outside of the UK:

Boston College, US: http://www.bc.edu/libraries/
Boston University, US: http://www.bu.edu/library/
Bibliothek am Guisanplatz
California State University, Sacramento: http://library.csus.edu/
Flinders University: http://www.flinders.edu.au/library/
Fort Hayes State University, US: http://www.fhsu.edu/library/
Free University of Bozen, Bolzano, Italy: http://www.unibz.it/en/library/welcome/default.html
Linfield College Library, part of Orbis Cascade Alliance: http://www.linfield.edu/linfield-libraries
KU Leuven: https://bib.kuleuven.be/english/ub
Midwestern State University, US: http://primo1.hosted.exlibrisgroup.com:1701/primo_library/libweb/action/search.do?
Monash University: http://www.monash.edu.au/library/
National University (US): http://www.nu.edu/
North Dakota State University: http://library.ndsu.edu/
Northeastern University, Boston: http://onesearch.northeastern.edu
NovoNordisk
Orbis Cascade Alliance: https://www.orbiscascade.org/shared-ils-1
Otago University: http://www.otago.ac.nz/library/
Purdue University: http://www.lib.purdue.edu/
Royal Melbourne Institute of Technology: http://www.rmit.com/library
Swinburne University of Technology, Adelaide: http://www.swinburne.edu.au/lib/
Texas Woman's University, US: http://www.twu.edu/library/default.asp
University of Adelaide: http://www.adelaide.edu.au/library/
University of Auckland, New Zealand: http://www.library.auckland.ac.nz/
University of Malta: https://www.um.edu.mt/library
University of Manitoba: http://umanitoba.ca/libraries/
University of Massachusetts – Dartmouth, US: http://www.library.umass.edu/
University of Minnesota: https://www.lib.umn.edu/
University of New South Wales: https://library.unsw.edu.au/
University of South Australia: http://library.unisa.edu.au/
Tarrant County College: http://library.tccd.edu
University of Texas, Dallas: http://www.utdallas.edu/library/
University of Western Sydney: http://library.uws.edu.au/uws_library/
Virginia Commonwealth University, US: http://www.library.vcu.edu/