[myTouch 3G, Magic Android Development] zuk_:
Thought that might be the problem too, so in the most recent wipe I used this instead of the HTC one.

It's still doing the random reboots, but maybe a bit less. I thought I went a full day without a reboot but noticed today that it was still doing it.

I tried keeping an eye on it with adb logcat to see what errors might be coming up, but ironically enough having the USB cable plugged in seems to stop the random reboots, so I'm having a hard time catching it in the act.

However, I did notice this in the logs at one point, and it *may* have coincided with a reboot:

W/dalvikvm( 3861): threadid=37: thread exiting with uncaught exception (group=0x4001e170)
E/AndroidRuntime( 3861): Uncaught handler: thread WindowManagerPolicy exiting due to uncaught exception
E/AndroidRuntime( 3861): *** EXCEPTION IN SYSTEM PROCESS. System will crash.
E/AndroidRuntime( 3861): java.lang.RuntimeException: Canvas: trying to use a recycled bitmap android.graphics.Bitmap@43b5e200
E/AndroidRuntime( 3861):	at android.graphics.Canvas.throwIfRecycled(Canvas.java:955)
E/AndroidRuntime( 3861):	at android.graphics.Canvas.drawBitmap(Canvas.java:980)
E/AndroidRuntime( 3861):	at com.android.internal.policy.impl.LockPatternKeyguardView$FastBitmapDrawable.draw(LockPatternKeyguardView.java:602)
E/AndroidRuntime( 3861):	at android.view.View.draw(View.java:6534)
E/AndroidRuntime( 3861):	at android.widget.FrameLayout.draw(FrameLayout.java:352)
E/AndroidRuntime( 3861):	at android.view.ViewGroup.drawChild(ViewGroup.java:1531)
E/AndroidRuntime( 3861):	at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1258)
E/AndroidRuntime( 3861):	at com.android.internal.policy.impl.KeyguardViewManager$KeyguardViewHost.dispatchDraw(KeyguardViewManager.java:85)
E/AndroidRuntime( 3861):	at android.view.View.draw(View.java:6552)
E/AndroidRuntime( 3861):	at android.widget.FrameLayout.draw(FrameLayout.java:352)
E/AndroidRuntime( 3861):	at android.view.ViewRoot.draw(ViewRoot.java:1332)
E/AndroidRuntime( 3861):	at android.view.ViewRoot.performTraversals(ViewRoot.java:1097)
E/AndroidRuntime( 3861):	at android.view.ViewRoot.handleMessage(ViewRoot.java:1613)
E/AndroidRuntime( 3861):	at android.os.Handler.dispatchMessage(Handler.java:99)
E/AndroidRuntime( 3861):	at android.os.Looper.loop(Looper.java:123)
E/AndroidRuntime( 3861):	at com.android.server.WindowManagerService$PolicyThread.run(WindowManagerService.java:511)
I/Process ( 3861): Sending signal. PID: 3861 SIG: 9

If 3861 is the process ID (sorry I'm a total noob to android), then a bit further up the following stuff shows up under this PID:

D/dalvikvm( 3861): GC freed 13345 objects / 637592 bytes in 185ms
V/WifiMonitor( 3861): Event [CTRL-EVENT-STATE-CHANGE id=-1 state=2]
V/WifiStateTracker( 3861): Changing supplicant state: DORMANT ==> SCANNING
V/WifiMonitor( 3861): Event [Trying to associate with 00:11:24:5d:e5:ff (SSID='*********' freq=2442 MHz)]
V/WifiMonitor( 3861): Event [CTRL-EVENT-STATE-CHANGE id=-1 state=3]
V/WifiStateTracker( 3861): Changing supplicant state: SCANNING ==> ASSOCIATING
V/WifiMonitor( 3861): Event [CTRL-EVENT-STATE-CHANGE id=1 state=4]
V/WifiStateTracker( 3861): Changing supplicant state: ASSOCIATING ==> ASSOCIATED
V/WifiMonitor( 3861): Event [Associated with 00:11:24:5d:e5:ff]
V/WifiMonitor( 3861): Event [CTRL-EVENT-STATE-CHANGE id=1 state=5]
V/WifiStateTracker( 3861): Changing supplicant state: ASSOCIATED ==> FOUR_WAY_HANDSHAKE
V/WifiMonitor( 3861): Event [CTRL-EVENT-STATE-CHANGE id=1 state=5]
V/WifiStateTracker( 3861): Changing supplicant state: FOUR_WAY_HANDSHAKE ==> FOUR_WAY_HANDSHAKE
V/WifiMonitor( 3861): Event [CTRL-EVENT-STATE-CHANGE id=1 state=6]
V/WifiStateTracker( 3861): Changing supplicant state: FOUR_WAY_HANDSHAKE ==> GROUP_HANDSHAKE
V/WifiMonitor( 3861): Event [CTRL-EVENT-STATE-CHANGE id=1 state=6]
V/WifiStateTracker( 3861): Changing supplicant state: GROUP_HANDSHAKE ==> GROUP_HANDSHAKE
V/WifiMonitor( 3861): Event [WPA: Key negotiation completed with 00:11:24:5d:e5:ff [PTK=TKIP GTK=TKIP]]
V/WifiMonitor( 3861): Event [CTRL-EVENT-STATE-CHANGE id=1 state=7]
V/WifiStateTracker( 3861): Changing supplicant state: GROUP_HANDSHAKE ==> COMPLETED
V/WifiMonitor( 3861): Event [CTRL-EVENT-CONNECTED - Connection to 00:11:24:5d:e5:ff completed (reauth) [id=1 id_str=]]

Hopefully this is of help to someone...