I've taken the old list and updated it to remove obsolete web addresses, and to add some new websites that have come on-line over the past 11 years. This thread would have been far more difficult to compile without the efforts of those previous posters. Míle buíochas, a chairde. I'm sure I've forgotten a few notable websites and resources, so feel free to add more or to contact the mods about adding more to the list.
Foclóirí 7 Téarmaíocht - Dictionaries & Terminology
- Teanglann
Dictionary and Language Library
http://www.teanglann.ie/en/
- An Fóclóir Beag (The Little Dictionary)
Irish dictionary, in Irish.
http://www.csis.ul.ie/focloir/
- Téarma
National Terminology Database for Irish
http://www.tearma.ie/
- Pota Focal
Foclóir Neamhspleách Gaeilge - Independent Irish Dictionary
http://www.potafocal.com/
- Foclóir.ie
Ongoing Irish dictionary and language resource project.
http://www.focloir.ie/
- Gramadach na Gaeilge
A short English-Irish grammar guide.
http://nualeargais.ie/gnag/gramadac.htm
- An Tobar
"Useful Irish Terms for the Public Sector"- getting around with the Irish language, - everything from going out to Government departments.
http://www.macsuibhne.com/bng/tobar/services.htm
- Téarmaí Ríomhaireachta
Computer terms (Irish language only)
http://www.smo.uhi.ac.uk/gaeilge/foc...riomhaire.html
- Gaelic Dictionaries Online
Web dictionaries for the different forms of the Gaelic languages, - Manx, Scottish and Irish
http://www.ceantar.org/Dicts/index.html
- Réimír
The Irish verb conjugator.
http://www.reimnigh.com/
- Verbix: Conjugation of Irish verbs
Useful page for learning grammar as Gaeilge
http://www.verbix.com/languages/irish.shtml
Na Meáin - Media
- TG4
Nationwide Irish language television station
http://www.tg4.ie/
- RnaG
RTÉ Raidió na Gaeltachta
http://www.rte.ie/rnag/
- Raidió na Life
106.4fm Cuisle na Cathrach (Baile Átha Cliath)
http://www.raidionalife.ie/ga/
- Raidió Rí-Rá
Cairt-staisiún ceoil é Raidió Rí-Rá a bhíonn ag craoladh go hiomlán trí Ghaeilge
http://www.rrr.ie/
- Raidió Fáilte
Stáisiún Raidió Pobail Gaeilge i mBéal Feirste
http://www.raidiofailte.com/
- Tuairisc
Online newspaper - news, information, analysis, opinion, and entertainment.
http://tuairisc.ie/
- PEIG
Lárphointe eolais don Ghaeilge/Information hub for the Irish language.
http://www.peig.ie/
- Nós
Iris chultúir a thugann léargas beoga Gaelach ar an saol thart orainn.
http://nos.ie/
- BBC Northern Ireland - Blas
BBC's beginners course in (Ulster) Irish.
http://www.bbc.co.uk/northernireland...rs/index.shtml
- GaelPort * OBSOLETE: Not updated since Easter 2014*
An Ghaeilge ar an Idirlíon - Irish language on the Internet - full of issues related to the Irish language.
http://www.gaelport.com/
- Pop-Up Gaeltacht
"Roghnaítear teach tabhairne uair sa mhí agus bailíonn Gaeil ann. Chun ól, like."
Pop-Up Gaeltacht
(mobile link: https://m.facebook.com/profile.php?id=936562433116447)
- Beo *ARCHIVE ONLY - LAST UPDATED 2014*
Ex-Irish language monthly internet magazine.
http://www.beo.ie/
Fóraim - Discussion Forums
- ILF
Irish Language Forum (including Irish Learners' Forum)
http://www.irishlanguageforum.com/
- Daltaí na Gaeilge
Irish language information and resources
http://www.daltai.com/home.htm
Facebook hosts a number of fantastic Irish-speaking groups.
Gaeilge Amháin *POSTS IN IRISH ONLY* (most notable, almost 9,000 members)
Díograiseoirí na Gaeilge (over 1,000 members)
Irish Language Learners' Forum (over 5,000 members)
- Irish Gaelic Translator
Useful phrases, Irish language classes worldwide, history of the language, and information on Ireland itself, in particular, Co. Clare.
http://www.irishgaelictranslator.com/
Siopaí Leabhar - Bookshops
- Litrocht
"Gach leabhar Gaeilge i gcló"
https://www.litriocht.com/
- An Siopa Leabhar
Conradh na Gaeilge bookshop
http://www.cnagsiopa.com/
- An Siopa Gaeilge
Bookshop of Oideas Gael
http://www.siopagaeilge.ie/store-13bpg1.htm
- An Ceathrú Póilí
Siopa neamhspleách leabhair Ghaeilge.
https://www.anceathrupoili.com/ga/
Seirbhísí 7 Achmhainní - Services & Resources
- Foras na Gaeilge
The body responsible for the promotion of the language
http://www.forasnagaeilge.ie/
- Oideas Gael
Adult Irish language and cultural classes
http://www.oideas-gael.com/en/
- Conradh na Gaeilge
Fóram daonlathach phobal na Gaeilge
https://www.cnag.ie/ga/
- Duolingo
Website and App for learning, practising, and acquiring new languages.
https://www.duolingo.com/course/ga/e...n-Irish-Online
- Memrise
An online learning tool with courses created by its community.
https://www.memrise.com/courses/english/irish/
- Ranganna
Foghlaim na Gaeilge ar-líne
http://ranganna.com/
- EGT
Irish language resources/Translation services
http://www.egt.ie/
- Cruinneog (GaelSpell)
Irish Spellcheckers and Grammar Checkers
http://www.cruinneog.com/
- Gaelic Languages Info
Listings of Irish classes around the world.
http://www.ceantar.org/
- WorldLanguage.com Language Store - Irish
Irish language books and other resources.
http://www.worldlanguage.com/Languag...ledFrom=210325
- Gaeilge ar an Ghréasán
Enormous index of Gaeilge links
http://www.smo.uhi.ac.uk/gaeilge/gaeilge.html
- Gaeilge Ar An Idirlíon *MANY OBSOLETE LINKS INCLUDED*
Large resource list (like this one

http://www.coisceim.ie/www.html
Medieval Irish Language and Literature
Legends, Poetry, Words of the day, Mailing lists, etc.
http://www.digitalmedievalist.com/urls/medirish.html
- Irish Phrases
New phrases to learn every month
http://www.ireland-information.com/irishphrases.htm
- An tInneal Mallachtaí
The Curse Engine

http://www.smo.uhi.ac.uk/gaeilge/don...ures/mallacht/
- Gàidhlig - English dictionary *Scottish Gaelic*
3.49Mb DOC file - Comprehensive (141 page) English-Gàidhlig & Gàidhlig-English dictionary in Microsoft Word Format.
http://www.smo.uhi.ac.uk/gaidhlig/we...r-gaidhlig.doc
Aipeanna - Apps for Mobile/Tablet devices
An Seinnteoir Raidió
Duolingo
--
Of course, a quick search on Google would also throw up a good few helpful sites.
Note that www.google.ie also features an Irish language version - is féidir é a úsáid trí Ghaeilge freisin

If you'd like to see anything added to this list, feel free to send a private message to Hullaballoo or An File with the relevant details.