One of Richter's finest recordings—I actually think, one of Bach's finest recordings overall:
The "Dorian" Toccata, BWV 538/1:
The choice of tempo is absolutely brilliant. It feels so simply right.
Also, the (in)famous Toccata by Charles-Marie Widor, played... by no less than Widor himself.
Widor started his career as assistant of Camille de Saint-Saëns, then organist at the Eglise de la Madeleine, and starting from 1870 he served for 63 years as titular organist of St. Sulpice in Paris—a record still unparalleled. He was also Professor of Organ at the Paris Conservatory from 1890, following César Franck's death. A man of great culture and learning, as a composer he is mostly known for his ten organ symphonies, some of which specifically written for the organ he was titular of.
He retired from his position at St. Sulpice in 1933, aged 89, and was succeeded by his former pupil Marcel Dupré. He died in Paris in 1937, aged 93.
The 'Toccata' is the last movement of Widor's 5th organ symphony, composed in 1879, and still remains his best-known work. It traditionally closes the Christmas Midnight Mass at St. Peter's Basilica in Vatican City.
Some question the fact that this recording is too slow and if you point out to them that the organist here is the composer himself, they would say that Widor was aging (he actually was, he was 88 years old when this concert was recorded) so he couldn't play faster.
Personally, I disagree. Also, Widor himself criticized the fact that his 'Toccata' became so popular because organists used it as a technical showoff, playing the piece at blazing fast tempos—it still happens, check Kalevi Kiniemi's version on YouTube.
Thirdly, the best interpretation I know of Boëllmann's 'Menuet Gothique'. It's the second movement of Boëllmann's best-known work, the 'Suite Gothique'. Olivier Latry is playing the Grand Orgue of Notre Dame de Paris—of which he is one of the four titular organists. The recording is taken from a recital held in 1994.
Finally, Marcel Dupré's Prelude and Fugue in G minor, op. 7/3, played by Yves Castagnet, titular organist of the choir organ of Notre Dame de Paris. Dupré composed his op. 7, a series of three preludes and fugues, when he was student at the Paris Conservatory. Widor, then Professor of Organ at the Conservatory, pronounced the first and the third (and particularly this one) unplayable. Matter of fact, Dupré remained the only organist able to play these works in public for years, until Léonce de Saint-Martin (would-be titular organist of Notre Dame from 1937, following Louis Vierne's death) played them to the satisfaction of Dupré's wife.
Dupré succeeded Widor as titular organist of St. Sulpice in Paris in 1934. He held the position until his death in 1971.
