Answer the question at the end by quoting:

Jan van Eyck (Dutch: ['jan van 'eik]) (before c. 1390 - 9 July 1441) was an Early Netherlandish painter active in Bruges. He is often considered one of the founders of Early Netherlandish painting, and, one of the most significant representatives of Northern Renaissance art.
It is known that van Eyck was considered revolutionary within his lifetime; his designs and methods were heavily copied and reproduced. His motto, one of the first and still most distinctive signatures in art history, ALS IK KAN ("AS I CAN"), a pun on his name, first appeared in 1433 on Portrait of a Man in a Turban, which can be seen as indicative of his emerging self-confidence at the time. The years between 1434 and 1436 are generally considered his high point when he produced works including the Madonna of Chancellor Rolin, Lucca Madonna and Virgin and Child with Canon van der Paele. He married the much younger Margaret probably around 1432, about the same time he bought a house in Bruges; she is unmentioned before he relocated, while the first of their two children was born in 1434. Very little is known of Margaret, even her maiden name is lost - contemporary records refer to her mainly as Damoiselle Marguerite. She is thought to have been of aristocratic birth, though from the lower nobility, evidenced from her clothes in this portrait which are fashionable but not of the sumptuousness worn by the bride in the Arnolfini Portrait. Later, as the widow of a renowned painter Margaret was afforded a modest pension by the city of Bruges after Jan's death. At least some of this income was invested in lottery. Van Eyck undertook a number of journeys on Philip the Duke of Burgundy's behalf between 1426 and 1429, journeys described in records as "secret" commissions, for which he was paid multiples of his annual salary. Their precise nature is still unknown, but they seem to involve his acting as envoy of the court. In 1426 he departed for "certain distant lands", possibly to the Holy Land, a theory given weight by the topographical accuracy of Jerusalem in The Three Marys at the Tomb, a painting completed by members of his workshop c. 1440. A better documented commission was the journey to Lisbon along with a group intended to prepare the ground for the Duke's wedding to Isabella of Portugal. Van Eyck's was tasked with painting the bride, so that the Duke could visualise her before their marriage. Because Portugal was ridden with plague, their court was itinerant and the Dutch party met them at the out of the way castle of Avis. Van Eyck spent nine months there, returning to the Netherlands with Isabella as a bride to be; the couple married on Christmas Day of 1429. The princess was probably not particularly attractive, and that is exactly how Van Eyck conveyed her in the now lost portrait. Typically he showed his sitters as dignified, yet did not hide their imperfections. After his return, he was preoccupied with completing the Ghent Altarpiece, which was consecrated on 6 May 1432 at Saint Bavo Cathedral during an official ceremony for Philip. Records from 1437 say that he was held in high esteem by the upper ranks of Burgundian nobility and was employed in foreign commissions.

what was special about it?

van Eyck was considered revolutionary within his lifetime;

Answer the question at the end by quoting:

Horslips are an Irish Celtic rock band that compose, arrange and perform songs frequently inspired by traditional Irish airs, jigs and reels. The group are regarded as 'founding fathers of Celtic rock' for their fusion of traditional Irish music with rock music and went on to inspire many local and international acts. They formed in 1970 and 'retired' in 1980 for an extended period. The name originated from a spoonerism on The Four Horsemen of the Apocalypse which became "The Four Poxmen of The Horslypse".
In March 2004, three Horslips enthusiasts, Jim Nelis, Stephen Ferris and Paul Callaghan, put on an exhibition of Horslips memorabilia in The Orchard Gallery in Derry. It was opened by the band, who played five songs acoustically. Buoyed by this first public appearance in 24 years, Horslips returned to the studio in Westmeath to produce a studio album, Roll Back, in the summer of 2004. Described as "Horslips Unplugged", the album contained acoustic reworkings of many of their best-known songs. The same exhibition moved to Drogheda in October 2005, courtesy of longtime fan Paddy Goodwin, and was formally opened on 6 October by a tribute band, Horslypse, composed of nine teenage musicians. Horslips did a version of "Furniture". The exhibition moved to Belfast in February and March 2006 and there were plans for a New York showing in 2007. In February 2008, the exhibition opened in Ballinamore in County Leitrim, and in July it opened in Ballybofey in Donegal. A double DVD entitled Return of the Dancehall Sweethearts came out in November 2005. Disc one is a documentary and disc two was live footage of the band from the 1970s, including promo videos and slots on The Old Grey Whistle Test. In December 2005, the band played in front of an invited audience for the recording of the RTE television program Other Voices in Dingle in County Kerry. Part of the set included three songs done "full-on" - the first time the band had played live and electric since October 1980. The last Horslips' event in this phase of their career was a TG4 tribute show recorded and broadcast live on 25 March 2006 before a live invited studio audience. A number of Irish personalities were interviewed, in Irish, about what the band meant to them and how Horslips shaped modern Irish music.

What happened with the return?
three Horslips enthusiasts, Jim Nelis, Stephen Ferris and Paul Callaghan, put on an exhibition of Horslips memorabilia in The Orchard Gallery in Derry.