There are several older post on the board about slosher trays or developing tray inserts. I've been using one of these (Sumitek Cradle) for the last year with 4x5 film and it works great. I moved up to 8x10 this past December and have been looking for the same type of tray for 8x10 without any luck. The other day I noticed that Photographer's Formulary is now selling their own version of the Cradle for 4x5 negatives so I decided to check with them to ask about a version for 8x10's. I just got off the phone with Bud at Photographers Formulary and he said that they are thinking about having a 8x10 negative version built and selling it on their website. If anyone is interested they might want to let him know that there is interest in a product like this. This is a link to the page for their 4x5 version in case anyone isn't familiar with slosher trays:

http://www.photoformulary.com/DesktopModules/StoreProductDetails.aspx?productID=856&tabid=0&tabindex=0&categoryid=0&selection=0&langId=0&Search=tray