Ask any Cannes veteran what they love most about the film festival and you'll get a multitude of different answers - for some it's the red carpet splash made by big name directors' latest films; for others it's the small but real possibility of getting into the same lift as Angelina Jolie. But for many, it's the opportunity to see the kind of offbeat little gem that might struggle to find an audience outside of the festival setting.

Cannes 2008 has provided a wealth of terrific movies which, for one reason or other, can be considered a tough sell. Take Tony Manero for example. It's the story of a psychopathic disco enthusiast set against the backdrop of Pinochet-era Chile. Raul is a stony-faced loner who idolises John Travolta's character in Saturday Night Fever. As the leader of a Saturday Night Fever tribute dance act, he dreams of stardom and will stop at nothing to get it, even when his ambition starts to accumulate a body count. In one memorable scene, Raul defecates on the white suit of a rival Travolta-wannabe to prevent him from competing in a televised lookalike competition. The menace of Pinochet's rule is manifested by the pair of government goons who periodically crop up to strike fear into the hearts of Raul's dance partners. It's a very dark, impeccably controlled portrait of a man driven to the brink of madness by disco.

Screening alongside Tony Manero in Directors' Fortnight is Eldorado, an occasionally surreal, frequently hilarious road movie from Belgium. Written and directed by, and also starring, Bouli Lanners, the film tells of Yvan (Lanners), a second-hand car dealer who surprises an inept burglar in his house. There's a stand off - the burglar refuses to come out from under the bed and relinquish the jar of small change he has purloined. But something in this gauche kid touches a nerve in the gruff Yvan, and he grudgingly agrees to drive him to his parents' house near the French border. The comedy is deadpan, employing sight gags and beautifully calibrated physical humour. It's a near flawless odd couple journey, definitely one to seek out at festivals and on DVD if a distribution deal fails to materialise.

Also currently without a distribution deal is Lion's Den, directed by Pablo Trapero (El Bonaerense, Born and Bred). The film, which screened in the main competition to acclaim, is set in a women's prison and stars the director's wife, Martina Gusman, as a pregnant middle-class student who, after an incident which left her boyfriend dead and his lover injured, finds herself in the mother and baby unit of a jail. Women in prison is the kind of subject that tends to get the melodramatic approach, but Trapero's matter-of-fact naturalism and Gusman's forceful performance serve the story brilliantly.

Great films with “difficult” subject matter often find it hard to secure a distribution deal. One such movie is the German picture Cloud 9, a raw examination of a love affair between a married woman in her sixties and a 76-year-old man. The sex scenes - and there are many of them - are tender and candid. The lovers' banter is ageless; their shared moments of laughter and their prickly arguments are recognisable to anyone, young or old. But the sympathetic and intelligent approach to the subject didn't make it any more palatable for the younger audience. One critic reported that his neighbour, a man in his twenties, covered his eyes every time the oldies got their rocks off. Exceptional acting notwithstanding, this film is unlikely to reach the audience it deserves.

Also from Germany is The Stranger in Me, an assured and utterly devastating account of postnatal depression. Screening alongside it in Critics' week is one of the festival's real oddities - Rumba an almost silent black comedy about a pair of ballroom dancers who are forced to reappraise their lives after he loses his memory and she loses a leg in a car accident. Not the easiest sell, but, like so many of the minor masterpieces in the sidebars at Cannes this year, it's worth seeking out.

For the latest news and reviews from the Cannes Film Festival visit timesonline.co.uk/cannes

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