At the very best, you might be able to make it go at your movement speed while hovering just over the ground and have it fall apart the first time it finds a pit trap, though it never makes clear how you'd direct it (what actions does it take to do so, for example?). Not much of a taxi. You really need Greater Floating Disk to do this right (a spell I've used that way quite a bit). Of course, if you meant Taxi like the hand cart taxis, then it works fine... you walk around, and carry your familiar or your party members on the disk. For this use it's good for making the big stupid fighter a bit quieter in his clanky armor (since he doesn't have to move while he's on your disk).
JaronK
