Image: FreeDigitalPhotos.net

Bubbl.us: http://bubbl.us powerful, easy to use mindmapping, charting application
Text2Mindmap: http://www.text2mindmap.com/ simple to use, type in outline, create
Diretory of mindmapping sites and services: http://mindmappingsoftwareblog.com/mmsb/wp-content/uploads/2009/08/index2.html
Wiki Mindmap: http://wikimindmap.com
Popplet: http://popplet.com Visual, presentation-type tool, includes YouTube-capability

NewsMap: http://newsmap.jp displays Google News headlines, by nation, colour-coded by topic
Newseum: Today's FrontPages: http://www.newseum.org/todaysfrontpages

Poster Generators
AutoMotivator: http://wigflip.com/automotivator/ use supplied or uploaded photos; quick, good quality

Online Publishing
Youblisher: http://www.youblisher.com/p/3925-Physics-Balsa-Bridge-Building-Contest/ (example)

Convert Webpage to PDF
PDFmyURL: http://pdfmyURL.com
PDFonFly: http://www.pdfonfly.com

Web Site/URL Sharing
Sqworl: http://sqworl.com Share web sites via annotated thumbnails, e.g. http://sqworl.com/n3bght

Statistical Data
Fake Name Generator: http://www.fakenamegenerator.com more than just names, entire profiles
Random numbers: http://www.random.org truly random numbers, generated from atmospheric noise

Word Maps
Wordle: http://wordle.net the app that put "wordles" on the map (NB: legal dispute interrupted service in late Feb 2010)
Techcrunch article on legal woes, trademark filing
Tagul: http://tagul.com not as sophisticated as Wordle but does offer embedding capability not found in Wordle
Tagxedo: http://www.tagxedo.com/app.html word clouds with shapes/styles
WordSift: http://wordsift.com "...linguistic playground that is available to instantly capture and display the vocabulary structure of texts..."

Chartle: http://chartle.net sophisticated features
Create-a-Graph: http://nces.ed.gov/nceskids/createagraph/default.aspx
Rich Chart Live: http://www.richchartlive.com/RichChartLive/
DIY Chart: http://www.diychart.com requires sign-up
Online Chart Generator: http://chartgen.blogspot.com
ChartGo: http://www.chartgo.com
Pie Chart Tool: http://www.mathcracker.com/pie_chart.php
Google Chart Tools: http://code.google.com/apis/charttools/index.html
Hohli Charts: http://charts.hohli.com line, bar, venn, scatter, radar charts

File Conversion
Zamzar: http://zamzar.com wide range of file conversions, including for YouTube URLs
DocsPal: http://www.docspal.com fast conversion of common doc and image types
Online-convert: http://www.online-convert.com/ no sign-up req'd, converts docs, images, videos, e-books, audio files

File Storage
Drop.io: http://drop.io create drops by adding nothing more than a name, e.g. drop.io/mydropbox, additional features

Transfer Large Files
TransferBigFiles.com http://www.transferbigfiles.com transfers via upload and emailed link to recipient

Highlighter for Web Pages
Awesome Highlighter: http://www.awesomehighlighter.com mark up your page with a yellow highlighter, add notes

RAR Extractor
Free RAR Extract Frog: http://download.cnet.com/Free-RAR-Extract-Frog/3000-2250_4-10804840.html?tag=mncol

Share Links
Fur.ly: http://fur.ly Add multiple URLs to a single link.

Starting Page Sites
LiveBinders: http://livebinders.com
Symbaloo: http://www.symbaloo.com

Task List Managers
Strike: http://www.strikeapp.com no sign-up required.
sandglaz: http://www.sandglaz.com grid-based task list manager, e-mail reminders