You could try basically boring your friend to tears. Whenever he IMs you, tell him you’re glad he contacted you, because you just HAVE to share this great idea about <insert incredibly boring/technical/geeky subject here>. Every time he tries to change the subject, switch it back.
“Hi, Fishbycycle! How are you doing?”
“Great! I just got a DCC setup for my HO scale trains. It took me all day to work the wiring out for the track plan. Let me tell you, using AC on the power bus is sheer genius. At first, I thought I was going to have trouble with my non-DCC locomotive, but I found a great adapter for it.”
“Oh, that sounds nice. Have you heard from Bob lately?”
“No. Did I mention the clerk at my train store is named Bob? What a coincidence, huh? Just yesterday he helped me work out the problem I was having with an induction motor in one of my locomotives…”
Oh, it also helps with the annoyance factor if you demand that they acknowledge your subject by asking them questions:
“Have you ever used a DCC unit for a model train?”
“Uh, no. I don’t even know what that is.”
“Oh, let me explain! It’s… <blah blah blah>. Doesn’t that sound cool? Did you have like an old HO set when you were a kid or anything?”
“No, I was never into trains. I was more a car guy.”
“But that’s the beauty! It doesn’t matter! If you like cars, you can build a cool model garage for your train setup! Have you ever seen how those model dioramas are put togther?”
Etc. Continue ad nauseum until friend decides he has better things to do with his time.
