Apologies to those of you who tried to view the Brain Damage site yesterday evening; due to some essential security and server work, our website hosts decided to run a major upgrade without prior notice. The site was therefore unavailable for around an hour and a half at one of our busier times.

However, we were able to keep updates flowing to those on the Brain Damage Facebook fanpage, which proved a great way for us to let people know what was going on. It's well worth joining - we also regularly have additional stuff on there which doesn't appear on the main site, and it's a great place for you to chat over all matters Floydian with your fellow fans. We look forward to welcoming you at Facebook.com/BrainDamageUK.

One of (many) highlights for attendees of the 2008 Syd Barrett "City Wakes" Festival in Cambridge were the guided tour of the city that took in many of the more significant sites which were connected to the life and times of Syd, and the various bands which lead to Pink Floyd.

Since then, the people behind the tour - personal friends of Syd, who grew up with him - have run their own special tours of Cambridge, to much acclaim.

As we told you back in March, they've now partnered with Brain Damage for a very special pair of tours, inviting you to discover some of Syd's 1960s Cambridge through the unique memories of those who knew him best, and who still live in the city. With some spaces left on both tours, we thought it best to remind you of the details so you can secure your place on what should be a fascinating look at the area.

Taking a break from his work on Roger Waters 2010 Wall tour, Gerald Scarfe is staging a special appearance at the Hay Literary Festival, an event he has been at previously to some acclaim. He'll be taking part in a discussion with Paul Gravett and Brian Griffiths about the history of satire, on June 5th 2010 at 5:30pm. More details of the event, and how to get tickets, here.

The discussion is a launch event for a new exhibition at the Tate Britain. "Rude Britannia: British Comic Art" runs from June 9th to 5th September 2010 and is a look at the artform from the 1600s to the present day, celebrating a rich history of cartooning and visual jokes.

As part of the exhibition, Gerald will be making another, surely unmissable appearance: Gerald Scarfe: Drawing a Laugh" on June 24th at 1pm, which will combine a history of his favourite characters and caricatures with a cartoon how-to, drawing live for the audience. Advance booking is essential, through this link.

Further to Monday's news that four more dates had been added to Roger Waters 2010 North American Wall tour (for Chicago, Philadelphia, Los Angeles and Anaheim), and in light of some emails we had asking for help, we thought it would be useful to remind you of the ticketing presale timetable for these concerts, as they fall outside the timetable used for the previously announced performances.

With the various presales, it can be quite confusing as there are a number of different ones available for each of the shows, and we want as many of you as possible to be able to secure your tickets. Amex Cardholders and RogerWaters.com presales at Ticketmaster.com have now started, but below we show you the other options open to you for each show.

While we're on the subject of the tour, don't forget to grab your free digital tour poster through this link!