Subliminal Messaging works best as an incentive for the Runner to run. Yes, that's right. An incentive.
Corp decks are at their most vulnerable when the Runner can "explode," and deal with several threats at once. A common "explosive" play is Account Siphon / Inside Job the scoring remote, while the ice is unrezzed. This play effectively counters most early scoring strategies on the corp's side. But notice that the runner has to get into HQ. Other, similar explosions also require successful runs--deep RnD digs; Account Siphon/ Vamp/ Data Leak Reversal; and so on. These all take resources, mostly in the form of credits, to pull off.
Subliminal Messaging offers the runner a choice: either start running every turn, or let the corp amass credits like a miser. If they want these clicks to be productive, then they have to start using credits and cards to get into servers, limiting their explosive ability.
Wasting a click from the runner each turn to deny the corp one free credit every turn is good for the corp, but letting the runner bounce off an Ice Wall is the worst use of this card. Runners with constant-pressure cards like Datasucker and Security Testing like making one run a turn, and can make corps regret their decision heavily.
So, there are two ways to take advantage of Subliminal. The first is to have cards that trigger off of runs, like Dedicated Response Team, Paywall Implementation, and, to a lesser extent, operations like SEA Source. These cards have the effect of making low-risk runs much more dangerous for the runner. Now the runner can either deal with those threats, or let the corp get one free credit a turn--which quickly builds up. Either way, the corp keeps pressure off while setting up scoring servers/windows.
The other way to make Subliminal messaging work is via lots of ICE that make it painful to face-check. Neural Katana, Enigma, and Pop-up Window all come to mind. These end up more effective than ETR ice in discouraging runs, since the runner can no longer bounce off painlessly. Unless the runner can break the ice, it's not getting run on. If they do break the ice, then you've probably made them spend more than a credit--taking away their economic advantage.
Subliminal, in terms of credit output, is much like PAD Campaign or Mental Health Clinic. It works best in decks with a longer gameplan, and in decks that might need to rapidly recover from going down to 0 credits. Rush decks aren't particularly invested in it, then, and decks that spam ETR ice might not want to bother. In certain, slow-playing decks with painful ice, this card shines, not because of the raw credit production, but because of how the runner has to respond.