In 1998, Breslin set up an Internet forum to discuss video games[1] which evolved into boards.ie, one of Ireland's largest indigenous websites.

[7] In 2011, he was announced as a co-founder of StreamGlider, a visual real-time dashboard for tracking interests across various types of devices, along with Nova Spivack and Bill McDaniel.

[14] Breslin's research publications have focused on the Social Semantic Web, and he co-authored two books on this topic in 2009 [15] and 2015.

[19][20] An Old Ireland in Colour book with some of these photographs, featuring captions written by historian Sarah-Anne Buckley, was published by Merrion Press in October 2020.

[31] Breslin has served as chair (cathaoirleach) of Gaillimh le Gaeilge since the end of 2023,[32] and was secretary of the American Council on Exercise from 2017 to 2019.