I measured the current consumption of the Teensy 3.0 at 24, 48 and 96MHz while it was running a do-nothing cpu loop consisting of a piece of a program that was posted on the Arduino forum. I used a 5.2VDC power supply.
The results are:

MHz ma
24 21.8
48 26.6
96 30.3



The on-board LED consumes 3ma.
When I find out how to put the beast to sleep I'll repeat the measurements.

Pete

Here's the code I used:
Code:
float sinanswers[1001];
float conanswers[1001];
float tananswers[1001];

void setup()
{
  Serial.begin(9600); // USB is always 12 Mbit/sec
  pinMode(13, OUTPUT);
  digitalWrite(13, 1);
}

int led_state = 1;
#define LOOP_COUNT 20
int loop_count = LOOP_COUNT;
void loop()
{

  if(loop_count-- == 0) {
    digitalWrite(13, led_state);
    led_state ^= 1;
    loop_count = LOOP_COUNT;
  }
  for (int i = 0; i < 1000; i++)
  {
    sinanswers[i] = sin(i);
    conanswers[i] = cos(i);
    tananswers[i] = tan(i);
  }
}