To celebrate 20 years of Walford & 45 years of Weatherfield, wouldn't it be excellent & a treat for viewers if for one week only, EastEnders & Corrie interacted. Of course it would never happen & would be too hard to film with schedules n that, but if it could 
For example, it could be a darts/football match, and the Vic happen to be playing at home to a Manchester team called the Rovers Return - Mike Baldwin could know a few characters already, Sarah Lou could get off with one of the EE lads (she's already been through most of the Corrie ones at how old...17? tart) and generally if scripted carefully it could be a laugh!
I remember back in 1995 in a special recorded message to EastEnders celebrating 10 years, Bet Lynch recieved a letter, all in cockney, from the Vic, about a football match, she had to get Mike to read it as they couldn't understand the lingo - it ended with the Corrie cast wishing the EE cast a happy Birthday

For example, it could be a darts/football match, and the Vic happen to be playing at home to a Manchester team called the Rovers Return - Mike Baldwin could know a few characters already, Sarah Lou could get off with one of the EE lads (she's already been through most of the Corrie ones at how old...17? tart) and generally if scripted carefully it could be a laugh!
I remember back in 1995 in a special recorded message to EastEnders celebrating 10 years, Bet Lynch recieved a letter, all in cockney, from the Vic, about a football match, she had to get Mike to read it as they couldn't understand the lingo - it ended with the Corrie cast wishing the EE cast a happy Birthday