I thought it would be fun and a good idea to list some tips, tricks, and secrets that we may have found throughout DAO that others can use as a reference. I know after being on this forum for a while that I've come across some things in DAO that I have always known but found that others didn't know and vice versa.
1) Sten's Cage in Lothering: I mentioned this in the "Revered Mother in Lothering" thread, but I'll list it here again in case people didn't see it there. When you meet Sten in Lothering, you can pick the lock on his cage yourself if you're a rogue or have Leliana do it. You DO NOT have to ask the Revered Mother for the key. Then bring him to the Chantry and enjoy people's reactions.
2) "Lost to the Memories" Quest in Orzammar: After returning the papers from Ortan Thaig to Orta in the Shaperate and then meeting her in the Assembly, you can ask her for a reward, and she will give you five sovereigns and you will get XP. Now for the extra part: Leave Orzammar and travel to anywhere else (the Party Camp doesn't count), then return to Orzammar and go revisit Orta in the Assembly. She will tell you about the success of her expedition to Ortan Thaig, and then she will give you an additional 10 sovereigns plus more XP. This was quite a nice little bonus.
3) Master Tilver: You will have to steal Master Tilver's key during the third stealing part of Slim Couldry's "Crime Wave" questline. Of course, you can walk up to him and flirt with him, stealing the key that way, or tell him you know him from Bann Darby's party, which gives you another option to steal the key. If you have a rogue with the Stealth ability and the Stealing skill, you can also sneak up and pickpocket the key from Master Tilver. There is yet another option, which I discovered during my current playthrough. Let me just say one thing: Master Tilver is a pervert and a pedophile! If you choose to do it this way (believe me, it was not my original intention. I was just trying to get close enough to steal without talking to him, and then I heard the guards chatting and decided to see what happened.), you will likely be disgusted. I know I was. But here it is if you're curious:
Take the route beside Goldanna's house, which brings you behind the Mages' Collective Liason. Walk very slowly and stop when the restless guard (he has Fenris' voice) starts talking to the other guard about a prostitute from the Pearl. Listen and wait for them to finish their conversation, then approach Tilver. The Fenris-voiced guard will stop you, so tell him you're from the Pearl. Tilver will order them to let you through. He will ask about Eloise, and you will have several options. Tell him she's running late because she wanted to make herself pretty for him. Here's where it gets disgusting. Tilver will then ask you if Eloise is truly "untasted." You will then have the option to either berate Tilver and call him a lech for wanting to sleep with a child, which will cause the Fenris-voiced guard to agree with you but tell you to leave, making it impossible to get the key that way; or you can confirm that Eloise is a virgin, which will please Tilver and cause the Fenris-voiced guard to leave because he is disgusted. Also, if you are a female Warden and you "praise" Tilver, he will tell you he would be interested in the female Warden if she were "younger." So gross. I wish there had been an option to slap Tilver or even to kill him.
4) "Summoning Sciences" Fourth Summoning Font: There is a fourth Summoning Font in the circular room that contains the stairs to the second level in the Circle Tower. It is behind the bookcases on the left. To activate this font, touch the Summoning Font in the main library room, click on all the objects from the first three fonts (follow the exact order from the first three Summoning Fonts but combine them together). Before you click the fourth Summoning Font, make sure you are controlling someone with the Stealing skill. Click the fourth Summoning Font, then QUICKLY steal from the man who appears (Arl Foreshadow). You will get a random inventory item, along with the codex "The Notes of Arl Foreshadow."
Anyone else have anything interesting they've discovered? List them here!