[Sony Ericsson Xperia Neo, Pro] tinyXperia:
This post has been on the XDA Developers portal frontpage!

Not everything is tested by me, using this is as always at own risk.

All firmwares

[APP] TTpod 3.0.1 Unofficial English translation

[APP] Reverse Tethering via USB

[APP] Opera Mobile 12 with extension support

[APP] MIUI Weather + Widget/clock for Europe and America

[TWEAK] Skipping lockscreen with menu button

[TWEAK] Disable wake with home button

[TWEAK][TIPS][4/7] Prototype Optimization

[TWEAK] lagfree G2X, ported to Xperia neo

[TOOL] WhatsApp message file analyzer, extractor and backup

[TOOL] Hot Nandroid backup: 'o-nandroid'

[THEME] My personal wallpaper collection [1] [2]

[THEME] HUGE wallpapers and icons collection

[THEME] MIUI V4 themes collection

[THEME] Custom offline charging animations

[MOD] Themes for Swiftkey, Swype Keyboards & ChompSMS

[FONT] Jelly Bean font - Roboto Slim

[MOD]Beats Audio +SRS +ALSA

Kernel modules for most CM10 kernels, use this when your wifi doesn't turn on

Jelly Bean

[TWEAK] Supremacy Script

[FONT] Flashable fonts for ICS and Jelly Bean

Jelly Bean Gapps AROMA installer for AOSP/CM10/AOKP ROMs

[KERNEL] FusioN kernel for CM10, AOKP 4.1 and MIUI V4.1

[MOD] LockScreen Weather Icons CM10/Paranoid/AOKP/PacMan

Ice Cream Sandwich

[TWEAK] Supremacy Script

[TWEAK] V6 Supercharger for Sony ICS

[TWEAK] Video driver mod (Adreno drivers for ICS)

[TWEAK] Improved responsiveness

[TWEAK] Enable software rendering in stock ICS for improved smoothness

[MOD] 10in1 SystemUI & Framework Mod

[MOD] Xperia Go settings menu by Pandemic

[MOD] Xperia T + Jelly Bean style statusbar

[MOD] Xperia T Lockscreen with shortcuts enabled

[MOD] On Screen buttons for MIUI V4 ROMs

[APP] Jelly Bean app pack for ICS

[APP] Xperia V Walkman

[APP] TouchWiz V4 Launcher (small resolution bug)

[APP] LG 3.0 Launcher

[APP][4.0.3+] MIUIMusic 2.3.9 for all 4.0.3 ROMS

[APP] A lot of Galaxy S3 apps

[APP] Google Now on your ICS phone

[MOD][4.0.4][Beta v1] ROM CONTROL Status Bar Mods for Stock SONY ROMS

Gingerbread

[THEME] Black and White Arc theme v7

[THEME] Ice Cream Sandwich

[THEME] XPERIA S by flamemo

[THEME] Full Xperia S theme

[THEME] 7 New Themes

[THEME] Horror by AUDIMEN

[THEME] Xperia 2012 Cosmic Flow

[THEME] Xperia Fran mod by morenoro

[THEME] XPERIA The GemS Series

[THEME] 3 Gingerbread themes by AUDIMEN

[THEME] Lockscreen theme

[GUIDE] Enable more homescreens on default launcher

[App] Xperia Active Launcher

[APP] TimeScape for non-stock ROMs

[APP] Xperia Flashlight

[MOD] Black Sony Ericsson Swype Keyboard

[MOD] Statusbar Widget, editable

[MOD] [PORT] HTC Beats Audio

[MOD] Battery percentage

[MOD] SE HOME 5x4 for 4.0.2.A.0.42 | source

[MOD] Modded Xperia S Launcher

[TWEAK] 30 steps media volume

[TWEAK] ZipITv7 [Tweaks,SpeedUP,bestRAM,Smoothness...]

[TWEAK] MegaBass

[TWEAK] V6 Supercharger for Gingerbread

[TWEAK] Supersmooth live wallpapers with this script

Guides and PC tools

Kernel Governors and I/O Schedulers

Definitive FAQ for MIUI V4/V4.1 porting

APK-tool, for decompiling and editing APK's

APK Multitool - Must have APK compiler, editer and modifier

APK manager, a simple script for modifying and decompiling APKs

5-minute guide on how to port ROM's between Arc-Ray-Neo

Related thread to this one on the Ray forum

Unpack kernels and modify Ramdisk

How to make 30 steps media volume framework.jar

How to enable USB Mass storage and on screen buttons in 4.x ROMs

Make your own fonts Android compatible

What is status 0, status 6 & status 7?

Useful commands in Terminal Emulator

QtAbd, an all-in-one tool for managing your phone via ADB

Total modding guide

On Screen Button mod guide

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