|Dungeon Magazine #97|
The very epic "Life's Bazaar" (written by the awesome Chris Perkins and featured in Dungeon #97 back in 2003) gave me the opportunity to fathom this query when I used it with a large group of players who had not one rogue between them and none of the questionable types had useful skills for bypassing locks and traps.
The adventure featured a forgotten and abandoned vault-like warren once inhabited by gnomes. Well, not quite abandoned and forgotten, as the adventure's villains did a small amount of slave trade with victims kidnapped from the urban sprawl above. As it happened, much of the maze-like enclave was protected by portals sealed with magic locks and traps.
So, what to do? I decided against forcing them to languish in the areas they could easily explore - I had too many players (10? I must have been mad) to entertain and the snooze factor could come into play in such a large dungeon. The monstrous foes could have given them the chance they needed - they played a hit and run strategy, but it's quite possible that their abilities to bypass magically sealed portals could benefit a fast and clever bunch of pursuers. Frankly, the group was too large to add an NPC trap expert - I had too much to do and even if I gave the NPC to a player to run, it was still another character to keep up with. I took another route altogether.
As the portals were magicked with wards and the like, it seemed to me that the parties arcane practitioners ought to have some power, or at least handy skills. I reasoned that if normal locks and traps were subject to deft hands and good ears (and maybe a nice set of thieving tools), then magical ones should be subject to Arcane Knowledge or Spellcraft skills. This solution brought the right kind of feel to the game and it got the wizard and sorcerer into saving the day in ways no one really expects - it was kind of cool describing how they would concentrate and make strange gestures to reveal secret runes encircling the ancient stone portals. Depending on how well they rolled on their skill checks, they either suppressed or disabled traps and locks.
Furthermore, it got the game moving in a way the players wanted to go. Even when their arcane skills failed to bypass certain portals, the players felt more in control of their destinies.
So this was kind of an ad hoc solution to a given situation, but it's something I have used a few times since. The Dungeons & Dragons game (and its spiritual successor, Pathfinder) always recommend creative and alternative skill check solutions for given challenges whenever possible. While I think Spellcraft always has a chance to be a winner for exploring magicked ruins and the like, you could easily replace Arcane Knowledge with Religion Knowledge (temples, undead lairs), Planar Knowledge (fiendish or alien domains) or Nature Knowledge (fey or druidic woods) - or whatever matches the nature of the adventure.
When I think about Gandalf, he seems to be the most adept and finding, bypassing, and setting up magically sealed portals out of any of the company he ran with in either The Hobbit or Lord of the Rings. Why can't my players' spellcasters be just as cool - and without necessarily having to expend precious spells?