I had the wifi dropping issue and after all the reading and tweaking and trying apps, changing the encryption on my router's wireless setting to TKIP only and my phone to static IP use fixed my issue. I got rid of all the apps minus Wifi Static.
Phone - DroidX running 2.2 - owned less than a week
Settings -> Wireless -> Wifi settings -> Menu -> advanced - unchecked 'Enable Auto IP' - set 'Use static IP' - manage IPs using Wifi Static
Router - Linksys WRT54G
Mode - G only
SSID broadcast - enabled
Security - WPA2 Personal
Encryption - TKIP
Key - 63 character
The following shouldn't matter, but here's the settings:
Wireless Filtering - enabled
Statically assigned DHCP by MAC - enabled
Both AES and AES/TKIP modes had issues where I needed to toggle wifi on my phone to get it reconnect after setting my phone down for 20 minutes
or so. Ever since forcing encryption to TKIP only last night and using a static IP, my connection has not dropped. This is what worked for me at least. Solid for 12 hours now - time will verify this.
There are a lot of threads out there ongoing regarding this issue however they're still ongoing so I figured this post could help vs being redundant.