true, I updated the list by removing the outdated tips.. this one should be about accurate. Credits go to Domgos

• Doing a ground slam with any melee weapon will destroy all nearby mines dropped by robots
• Tapping space during a cinematic (beginning of missions and bosses) will prompt you with a skip cinematic interface , tapping space again will skip the cinematic
• The number displayed everytime a kill occurs is experience
• When fusing mods, fusing the same mod together will give you 100% experience towards leveling it. Fusing two mods with the same polarity (the little symbols on the top right) will grant you 50% experience and fusing two mods that have nothing related will give you 25% experience. (simmobl1)
• A great planet to farm experience solo (or even in group) is Venus - Fossa. Not only do the moas give you good experience (Around 260 per kill) but you then kill Jackal for additional experience. Here's a link to my short guide : https://www.youtube.com/watch?v=dbxX7Q4uKfk
• Red orbs give you +25 health back, blue orbs will give you +25 mana when dropped from ennemies and +50 mana when dropped from containers. Also white balls will give you +100 Affinity (Experience) for your currently equiped warframe.
• Press "Q" to open your inventory and have access to the items you put in there
• You can switch position with your Decoy using your teleportation ability (jefrejtor)
• Half of the squad must reach the end for the countdown to tick
• Blueprints look like white affinity orbs with a pink color instead.
• Doing a slide attack (Sprint+Crouch+Attack) will allow you to go through lasers
• Press "Z" to see your party members , their level as well as their current health/shield (Noneerror)
• Some abilities will also allow you to go through lasers, like Excalibur's dash and Loki's stealth (AvidLoLFan)
• Your warframe, your main weapon, your secondary as well as your melee weapon all have individual levels. Leveling any of these will contribute to leveling your profile level (Max level warframes and weapons do not contribute to your profile level experience)
• Your profile level allows you to unlock weapons that can then be bought, the highest level required is level 7 for the "Supra" (weapon acquired from clan crafting system)
• Crit chance mods will not grant you as much crit chance as it is written, instead you will gain a crit chance amount equal to the base crit chance of the weapon. (7.5% base crit chance on a weapon with a 100% crit mod increases your crit chance to 15% not 107.5%)
• Armor penetration will allow you to deal damage to enemies in areas they cannot normally be damaged and/or deal extra damage. For exemple corpus crewman will take severe damage when shot to the head with armor penetration mods
• Ancient infecteds have weakspots in their arms and legs ! (confuseray)
• Grineer Seekers will drop down rolling grenades that will stick to you, by rolling (tap shift) they will fall off you (azkabaal) This is also true with leech drones when they're stuck to you. (Seymor569)
• Lasers and turrets are activated by cameras on Corpus maps. If any player is seen on any camera all the lasers on the map will activate. (azkabaal)
• Pressing "H" will switch your camera position , which can be sometimes useful to shoot enemies from different angles. (confuseray) Tip: Rebind this key to your middle-mouse button for easy access.