The right squire of legend can help in these specific cases…
A creature that takes the prestige class squire of legend (Complete Champion 110–2), picks as his paragon's path the fallen hero Reikhardt, and advances to level 2 gains Reikhardt's lesser squire's burden, a supernatural ability usable once per day that says
You can grant an ally within 30 feet a second use of an extraordinary or supernatural ability normally usable only once per day. If you gain a second daily use of this [lesser squire's burden] ability, you cannot use it twice in one day on the same ally.
While this means there's a dude following around and cheering on your swashbuckler/dervish, that's actually kind of in genre. (The text says specifically that a squire can't use these kinds of abilities on himself, although possibly a squad of squires of legend could use them on each other. Ask the DM.)
Otherwise, however, Topquark's pretty much nailed it in that if you're looking for another Wizards of the Coast way to get extra uses of a class feature generally, you're out of luck and left hoping something was published that increases the number of times that class feature specifically can be used.
…And you can also look to licensed material
AEG's The Hidden Emperor (2005)—a Wizards of the Coast officially licensed product—includes the feat Heart of Suitengu (16), which has as its benefit the following:
Once per day, by taking 1 hour to meditate and spending a Void Point, you may select one Class Feature that has a limited number of uses per day (other than Spells and Spell Use); your number of uses refreshes as though you had spent a day of rest.
The Heart of Suitengu feat's prerequisites are 1 level of monk, shugenja, or inkyo (a setting-specific base class from Rokugan 41-4—also a Wizards of the Coast officially licensed product) plus the feat Void Use (55-6), the latter feat making this feat challenging for a nonhuman, non-Rokugani creature to acquire. There's an argument that allows even a nonhuman, non-Rokugani with but 1 level of inkyo to gain the feat Void Use then to take immediately—as the creature's level 1 inkyo kiho feat (similar to a fighter's bonus feat)—the feat Heart of Suitengu.
If you've already one level of inkyo, monk, or shugenja, an even more generous DM may allow you to take the feat Heart of Suitengu upon acquiring "all the advantages of the Void Use feat" via the amulet of the void (Secrets of the Phoenix 61—still officially licensed) (8,000 gp; 0 lbs.).
Were I the DM for a traditional Dungeons and Dragons 3.5 campaign in which a player wanted the feat Heart of Suitengu so his PC dervish's a thousand cuts or swashbuckler's lucky extraordinary abilities could be used a second time per day, I'd have no problem with the PC taking one level of inkyo to get the feat (or whatever workaround's needed to meet the feat Heart of Suitengu's prerequisites). I would, however, look askance at a player who, for example, wanted his PC to take a level of inkyo so that as a level 10 master of the secret sound (Dragon #297 78-9) the PC could use the spell-like ability the secret sound a second time per day. (I mean, really wish as a spell-like ability once per day should be enough.)
