Many of the best moments in gaming arrive by mistake. Experimentation, exploration, glitches, stumbling across areas of the game that you weren't supposed to - or the developers never expected you to find. Below are ten of our favourites from this generation of consoles. Agree? Disagree? Tell us about your favourite secrets in the comments below...
1. BATMAN: ARKHAM ASYLUM
Is this the daddy of all gaming secrets? Developers Rocksteady hid it so well that it remained undetected for an entire year.
Destroying a wall panel to your left as you face the fireplace in Warden Quincy Sharp's office provides access to a hidden room. But there's a catch. Unlike every other destructible wall in Arkham Asylum, this one doesn't show up in Detective Mode. As a cheeky added extra, the wall panel is also super-strong, needing all three explosive gel applications to detonate at once in order to make the break through.
Post-Arkham City it's easy to forget what a massive reveal lay inside: a secret area containing reams of hints about Asylum's as-yet-unannounced sequel, including an 'approved' blueprint of Arkham City itself, and a slew of concept art. Think about it: there was a full reveal for Arkham Asylum's follow-up right there, the whole time, from minute one.
Is there an equivalent in City? As yet, no one's found it - but given Rocksteady's previous and the fact that Game Director Sefton Hill recently told us that gamers had found most but not all of City's secrets, we wouldn't bet against it.
2. THE ELDER SCROLLS V: SKYRIM
The Throat of the World is the highest mountain in Skyrim, towering over the lands of Tamriel, and the top of it can only be reached legitimately by completing the quest of the same name.
Once up there, climbing further to the summit and searching around reveals the Notched Pickaxe, a unique pickaxe that gives you a boost to your Smithing skill and delivers shock damage when used as a weapon.
This is probably a reference to 'Notch', the creator of Minecraft, as pickaxes feature heavily in that game and Smithing is similar to the crafting which takes place in Minecraft.
3. PORTAL 2
Throughout the course of Portal 2 there are a number of 'Rat Man dens', hidden areas with walls covered in scrawled writing and drawings by a surviving Aperture scientist. One of these contains an extra secret.
When traversing Test Chamber 6, pressing the switch on the far side for the first time drops several items of rubbish including a radio. Collect this and return to the start of the Test Chamber. Reposition your second portal on the wall above the angled section you used to cross the area and you'll be launched into one of these dens.
Carry the radio deeper into the room and the cheery music will be replaced with the sound of a data transmission. Now here comes the really secret part. That transmission sound is actually a slow-scan television (SSTV) signal, which when decoded with the appropriate software creates an image of a companion cube on the Moon - a clear reference to the game's lunar conclusion.